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1.
Int J Neonatal Screen ; 10(1)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38390980

RESUMO

Congenital hypothyroidism (CH) leads to growth and development delays and is preventable with early treatment. Neonatal screening for CH was initiated in Portugal in 1981. This study examines the history of CH screening in the country. Data were obtained from annual reports and from the national database of neonatal screening laboratory. The CH screening strategy primarily relies on the thyroid-stimulating hormone (TSH), followed by total thyroxine measurement as the second tier for confirmation. The TSH cutoff started at 90 mIU/L, decreasing to the actual 10 mIU/L. The coverage of the screening program has increased rapidly; although voluntary, it reached about 90% in 6 years and became universal in 10 years. Guideline and cutoff updates led to the identification of over 200 additional cases, resulting in specific retesting protocols for preterm and very-low-birth-weight babies. The actual decision tree considers CH when TSH levels are above 40 mIU/L. Data from the CH screening also provide an indication of the iodine status of the population, which is presently indicative of iodine insufficiency. The Portuguese neonatal screening for CH is a history of success. It has rapidly and continuously adapted to changes in knowledge and has become a universal voluntary practice within a few years.

2.
Nutrients ; 15(20)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37892522

RESUMO

Mild-to-moderate iodine deficiency during pregnancy is prevalent worldwide, but its consequences for maternal and child health are not clear. We aimed to investigate the impact of maternal iodine intake during pregnancy on the child's growth and neurodevelopment. This study involved a cohort of 11-year-old children (n = 70) whose mothers had participated in an iodine intake survey during pregnancy. Gestational, neonatal, anthropometric, intelligence quotient (IQ), and socioeconomic parameters were analyzed according to maternal urinary iodine concentration (UIC). There was a positive linear trend of current height Z-score, full-scale IQ, verbal IQ, family income, maternal education, and a negative trend of neonatal TSH levels with increasing maternal UIC levels. However, regression analysis indicated that maternal UIC was not an independent predictor of any gestational, neonatal, or childhood development parameter. Only maternal school education was positively associated with child height and IQ. In conclusion, we did not find any evidence of a direct effect of maternal iodine intake during pregnancy on the long-term growth and neurodevelopment of children. The results suggest that socioeconomic factors are important confounding factors that affect both maternal iodine intake and child development and must be considered when investigating the association between maternal iodine intake and child outcomes.


Assuntos
Iodo , Gravidez , Feminino , Recém-Nascido , Humanos , Criança , Seguimentos , Desenvolvimento Infantil , Mães , Estado Nutricional
3.
Artigo em Inglês | MEDLINE | ID: mdl-37711122

RESUMO

INTRODUCTION: Newborn screening (NBS) in Portugal is a significant public health measure to provide early detection for specific disorders so that early treatment is possible. Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder that causes degeneration of anterior horn cells in the human spinal cord and subsequent loss of motor neurons. Its incidence is estimated in 1.6000-11.800 live births. A pilot study on 100.000 newborns is being carried out at the neonatal screening laboratory with the aim of determining the specificity, sensitivity, and feasibility of the SMA screening at the NBS laboratory in Portugal. METHODS: The study presented here was based on data obtained from neonatal screening, involving the analysis of 25.000 newborns. SMA screening is performed by a qualitative detection of exon 7 of the SMN1 gene. The assay was performed using a commercially available real-time PCR, the Eonis SMN1, TREC, and KREC kit. RESULTS/CASE REPORT: The dried blood spots of a total of 25.000 newborns were tested; among these newborns, two were diagnosed as having SMA with survival motor neuron 1 (SMN1) deletion. These two SMA-positive samples were sent to a specialized clinical centre and a peripheral blood sample was sent to the reference laboratory for confirmation of the exon 7 deletion and determination of the SMN2 copy number. CONCLUSION: Early diagnosis and intervention are important for SMA treatment to be effective; the treatment should be started at the pre-symptomatic stage of SMA. Thus, newborn screening for SMA is strongly recommended. Currently, targeted therapies for SMA are available, and attempts are being made worldwide to include SMA screening in newborns.

4.
Int J Mol Sci ; 23(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36499116

RESUMO

Alzheimer's disease (AD) is a progressive and complex neurodegenerative disease. Acetylcholinesterase inhibitors (AChEIs) are a major class of drugs used in AD therapy. ROCK2, another promising target for AD, has been associated with the induction of neurogenesis via PTEN/AKT. This study aimed to characterize the therapeutic potential of a novel donepezil-tacrine hybrid compound (TA8Amino) to inhibit AChE and ROCK2 protein, leading to the induction of neurogenesis in SH-SY5Y cells. Experiments were carried out with undifferentiated and neuron-differentiated SH-SY5Y cells submitted to treatments with AChEIs (TA8Amino, donepezil, and tacrine) for 24 h or 7 days. TA8Amino was capable of inhibiting AChE at non-cytotoxic concentrations after 24 h. Following neuronal differentiation for 7 days, TA8Amino and donepezil increased the percentage of neurodifferentiated cells and the length of neurites, as confirmed by ß-III-tubulin and MAP2 protein expression. TA8Amino was found to participate in the activation of PTEN/AKT signaling. In silico analysis showed that TA8Amino can stably bind to the active site of ROCK2, and in vitro experiments in SH-SY5Y cells demonstrate that TA8Amino significantly reduced the expression of ROCK2 protein, contrasting with donepezil and tacrine. Therefore, these results provide important information on the mechanism underlying the action of TA8Amino with regard to multi-target activities.


Assuntos
Doença de Alzheimer , Inibidores da Colinesterase , Neuroblastoma , Doenças Neurodegenerativas , Quinases Associadas a rho , Humanos , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Inibidores da Colinesterase/química , Donepezila/farmacologia , Neuroblastoma/tratamento farmacológico , Doenças Neurodegenerativas/tratamento farmacológico , PTEN Fosfo-Hidrolase , Quinases Associadas a rho/antagonistas & inibidores , Tacrina/química
5.
EJNMMI Radiopharm Chem ; 7(1): 26, 2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36201072

RESUMO

BACKGROUND: 2-[18F]Fluoroethyltosylate ([18F]FEtOTs) is a well-known 18F-fluoroalkylating agent widely used to synthesize radiotracers for positron emission tomography. The widespread use of [18F]FEtOTs is due in part to its low volatility when compared to other halide and sulfonate building blocks. In this work, the radioactive volatile side-products formed during the synthesis of [18F]FEtOTs were identified and characterized for the first time, and an optimization of the reaction conditions to minimize their formation was proposed. RESULTS: In order to characterize the volatiles produced during [18F]FEtOTs synthesis, the reaction mixtures of both cold FEtOTs and [18F]FEtOTs were co-injected onto the HPLC system. The radioactive peaks corresponding to the volatile compounds were collected, analyzed through headspace gas chromatography mass spectrometry sampler (HS-GC-MS) and identified as vinyl fluoride ([19F]VF) and 2-fluoroethanol ([19F]FEOH). By using a rotatable central composite design with a two-level full factorial core of two factors (22), it was determined that temperature and time are independent variables which affect the generation of [18F]VF and [18F]FEOH during the radiosynthesis of [18F]FEtOTs. In addition, in order to reduce the formation of the volatiles ([18F]VF and [18F]FEOH) and increase the yield of [18F]FEtOTs, it was demonstrated that the molar ratio of base to precursor must also be considered. CONCLUSION: [18F]VF and [18F]FEOH are volatile side-products formed during the radiosynthesis of [18F]FEtOTs, whose yields depend on the reaction time, temperature, and the molar ratio of base to precursor. Therefore, special care should be taken during the radiosynthesis and subsequent reactions using [18F]FEOTs in order to avoid environmental contamination and to improve the yield of the desired products.

6.
J Alzheimers Dis Rep ; 6(1): 177-193, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35591949

RESUMO

Alzheimer's disease (AD) is a slowly progressive neurodegenerative disease conceptualized as a continuous process, ranging from mild cognitive impairment (MCI), to the mild, moderate, and severe clinical stages of AD dementia. AD is considered a complex multifactorial disease. Currently, the use of cholinesterase inhibitors (ChEI), such as tacrine, donepezil, rivastigmine, and galantamine, has been the main treatment for AD patients. Interestingly, there is evidence that ChEI also promotes neuroprotective effects, bringing some benefits to AD patients. The mechanisms by which the ChEI act have been investigated in AD. ChEI can modulate the PI3K/AKT pathway, which is an important signaling cascade that is capable of causing a significant functional impact on neurons by activating cell survival pathways to promote neuroprotective effects. However, there is still a huge challenge in the field of neuroprotection, but in the context of unravelling the details of the PI3K/AKT pathway, a new scenario has emerged for the development of more efficient drugs that act on multiple protein targets. Thus, the mechanisms by which ChEI can promote neuroprotective effects and prospects for the development of new drug candidates for the treatment of AD are discussed in this review.

7.
Eur Thyroid J ; 11(1)2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34981750

RESUMO

Objectives: Over 1.9 billion people worldwide are living in areas estimated to be iodine insufficient. Strategies for iodine supplementation include campaigns targeting vulnerable groups, such as women in pre-conception, pregnancy and lactation. Portuguese women of childbearing age and pregnant women were shown to be mildly-to-moderately iodine deficient. As a response, in 2013, the National Health Authority (NHA) issued a recommendation that all women considering pregnancy, pregnant or breastfeeding, take a daily supplement of 150-200 µg iodine. This study explored how the iodine supplementation recommendation has been fulfilled among pregnant and lactating women in Portugal, and whether the reported iodine supplements intake impacted on adverse obstetric and neonatal outcomes. Design and methods: Observational retrospective study on pregnant women who delivered or had a fetal loss in the Braga Hospital and had their pregnancies followed in Family Health Units. Results: The use of iodine supplements increased from 25% before the recommendation to 81% after the recommendation. This was mostly due to an increase in the use of supplements containing iodine only. Iodine supplementation was protective for the number of adverse obstetric outcomes (odds ratio (OR) = 0.791, P = 0.018) and for neonatal morbidities (OR = 0.528, P = 0.024) after controlling for relevant confounding variables. Conclusion: The recommendation seems to have succeeded in implementing iodine supplementation during pregnancy. National prospective studies are now needed to evaluate the impact of iodine supplementation on maternal thyroid homeostasis and offspring psychomotor development and on whether the time of the beginning of iodine supplementation (how early during preconception or pregnancy) is relevant to consider.

8.
Bioorg Chem ; 113: 104982, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34020277

RESUMO

ERK1/2 inhibitors have attracted special attention concerning the ability of circumventing cases of innate or log-term acquired resistance to RAF and MEK kinase inhibitors. Based on the 4-aminoquinazoline pharmacophore of kinases, herein we describe the synthesis of 4-aminoquinazoline derivatives bearing a 1,2,3-triazole stable core to bridge different aromatic and heterocyclic rings using copper-catalysed azide-alkyne cycloaddition reaction (CuAAC) as a Click Chemistry strategy. The initial screening of twelve derivatives in tumoral cells (CAL-27, HN13, HGC-27, and BT-20) revealed that the most active in BT-20 cells (25a, IC50 24.6 µM and a SI of 3.25) contains a more polar side chain (sulfone). Furthermore, compound 25a promoted a significant release of lactate dehydrogenase (LDH), suggesting the induction of cell death by necrosis. In addition, this compound induced G0/G1 stalling in BT-20 cells, which was accompanied by a decrease in the S phase. Western blot analysis of the levels of p-STAT3, p-ERK, PARP, p53 and cleaved caspase-3 revealed p-ERK1/2 and p-STA3 were drastically decreased in BT-20 cells under 25a incubation, suggesting the involvement of these two kinases in the mechanisms underlying 25a-induced cell cycle arrest, besides loss of proliferation and viability of the breast cancer cell. Molecular docking simulations using the ERK-ulixertinib crystallographic complex showed compound 25a could potentially compete with ATP for binding to ERK in a slightly higher affinity than the reference ERK1/2 inhibitor. Further in silico analyses showed comparable toxicity and pharmacokinetic profiles for compound 25a in relation to ulixertinib.


Assuntos
Antineoplásicos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/farmacologia , Triazóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Quinazolinas/química , Relação Estrutura-Atividade , Triazóis/química
10.
Rev Esp Salud Publica ; 952021 Jan 26.
Artigo em Espanhol | MEDLINE | ID: mdl-33496269

RESUMO

The Portuguese Newborn Screening Program is a public health program that started in 1979, screening for PKU, being totally supported by public funds. It's a non-mandatory well implemented program that testes about 99.9% of Portuguese newborns. In the actual screening panel encompasses 26 disorders, including inborn errors of metabolism, congenital hypothyroidism and cystic fibrosis. Sample collection is advised to be made at 3rd day of life and treatment begins in average by the 10th day. Every testes are performed in one single national laboratory, that processes about 88,000 samples/year. In the 41 years of program existence, more than 3,800,000 newborns were screened and 2,130 affected newborns detected, reflecting the positive impact of the Program in the population. Future perspectives include the increase of program value in terms of public health by optimizing the screening of the disorders already screened and evaluation the possibility of adding others.


El Programa Portugués de Cribado Neonatal es un programa de Salud Pública a nivel nacional, que tuvo su inicio en 1979 con el cribado de la fenilcetonuria y es financiado totalmente por el Estado portugués. Se trata de un programa no obligatorio, con una tasa de cobertura del 99,8%, en el que hoy en día se criban veintiséis enfermedades, incluyendo metabolopatías, hipotiroidismo congénito y fibrosis quística. La toma de muestra se hace al 3er día de vida y el tratamiento de los neonatos afectos empieza en torno al 10º día. Todos los análisis están centralizados en un único laboratorio, que procesa aproximadamente 88.000 muestras al año. En los últimos cuarenta y un años se cribaron más de 3.800.000 neonatos y se detectaron 2.130 niños afectados, lo que es un indicador del impacto del programa en la población. Los desafíos futuros incluyen la búsqueda de nuevas estrategias para incrementar el valor del programa, donde se evalúen nuevas enfermedades a cribar y la optimización del cribado actual.


Assuntos
Triagem Neonatal , Humanos , Recém-Nascido , Portugal , Avaliação de Programas e Projetos de Saúde
11.
Anticancer Agents Med Chem ; 21(12): 1602-1611, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33081686

RESUMO

BACKGROUND: Several metal-based molecules that display cytotoxicity against multiple cell lines have been pursued in an attempt to fight against cancer and to overcome the typical side effects of drugs like cisplatin. In this scenario, ruthenium complexes have been extensively studied due to their activity in both in vitro and in vivo biological systems, including various cancer cell strains. OBJECTIVE: We aimed to develop a method to synthesize novel [Ru(NO)(bpy)2L2]2+ complexes containing amino acid ligands by using an alternative Click Chemistry approach, namely the copper azide-alkyne cycloaddition reaction (CuAAC reaction), to construct nitrosyl/nitrite complexes bearing a modified lysine residue. METHODS: We synthesized a new ligand by Click Chemistry approach and new compounds bearing the unprecedented ligand. Cytotoxicity was assessed by the classical MTT colorimetric assay. MCF-7 and MDAMB- 231 cells were used as breast cancer cell models. MCF-10 was used as a model of healthy cells. RESULTS: Amino acid ligands related to N3-Lys(Fmoc) and the new pyLys were successfully synthesized by the diazotransfer reaction and the CuAAC reaction, respectively. The latter reaction involves coupling between N3-Lys(Fmoc) and 3ethynylpyridine. Both N3-Lys(Fmoc) and the new pyLys were introduced into the ruthenium bipyridine complex I, or cis-[RuII(NO)(NO2)(bpy)2]2+, to generate the common nitro-based complex III, which was further converted to the final complex IV. Results of the MTT assay proved the cytotoxic effect of cis- [RuII(NO)(pyLysO-)(bpy)2](PF6)2 against the mammalian breast cancer cells MCF-7 and MDA-MB231. CONCLUSION: The viability assays revealed that complex IV, bearing a NO group and a modified lysine residue, was able to release NO and cross tumor cell membranes. In this work, Complex IV was observed to be the most active ruthenium bipyridine complex against the mammalian breast cancer cells MCF-7 and MDA-MB231: it was approximately twice as active as cisplatin, whilst complexes I-III proved to be less cytotoxic than complex IV. Additional tests using healthy MCF 10A cells showed that complexes II-IV were three- to sixfold less toxic than cisplatin, which suggested that complex IV was selective against cancer cells.


Assuntos
2,2'-Dipiridil/farmacologia , Aminoácidos/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Complexos de Coordenação/farmacologia , Óxido Nítrico/farmacologia , Rutênio/farmacologia , 2,2'-Dipiridil/química , Aminoácidos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Teoria da Densidade Funcional , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Ligantes , Estrutura Molecular , Óxido Nítrico/química , Rutênio/química , Relação Estrutura-Atividade
12.
Bioorg Med Chem ; 28(22): 115746, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-33007558

RESUMO

Human T cell lymphotropic virus type 1 (HTLV-1) is a human retrovirus that infects approximately 10-20 million people worldwide and causes an aggressive neoplasia (adult T-cell leukemia/lymphoma - ATL). Therapeutic approaches for the treatment of ATL have variable effectiveness and poor prognosis, thus requiring strategies to identify novel compounds with activity on infected cells. In this sense, we initially screened a small series of 25 1,2,3-triazole derivatives to discover cell proliferation inhibitors and apoptosis inducers in HTLV-1-infected T-cell line (MT-2) for further assessment of their effect on viral tax activity through inducible-tax reporter cell line (Jurkat LTR-GFP). Eight promising compounds (02, 05, 06, 13, 15, 21, 22 and 25) with activity ≥70% were initially selected, based on a suitable cell-based assay using resazurin reduction method, and evaluated towards cell cycle, apoptosis and Tax/GFP expression analyses through flow cytometry. Compound 02 induced S phase cell cycle arrest and compounds 05, 06, 22 and 25 promoted apoptosis. Remarkably, compounds 22 and 25 also reduced GFP expression in an inducible-tax reporter cell, which suggests an effect on Tax viral protein. More importantly, compounds 02, 22 and 25 were not cytotoxic in human hepatoma cell line (Huh-7). Therefore, the discovery of 3 active and non-cytotoxic compounds against HTLV-1-infected cells can potentially contribute, as an initial promising strategy, to the development process of new drugs against ATL.


Assuntos
Antivirais/farmacologia , Produtos do Gene tax/antagonistas & inibidores , Compostos Heterocíclicos/farmacologia , Vírus Linfotrópico T Tipo 1 Humano/efeitos dos fármacos , Triazóis/farmacologia , Antivirais/síntese química , Antivirais/química , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Produtos do Gene tax/metabolismo , Compostos Heterocíclicos/química , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Triazóis/química
13.
Carbohydr Res ; 498: 108155, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33010570

RESUMO

The synthesis of MUC1 glycopeptides bearing modified tumor-associated carbohydrate antigens (TACAs) represents an effective strategy to develop potential antitumor vaccines that trigger strong immune response. In this context, we present herein the multistep synthesis of the triazole glycosyl amino acid Neu5Ac-α/ß2-triazole-6-ßGalNAc-ThrOH 1 as STn antigen analog, along with its assembly on the corresponding MUC1 peptide to give NAcProAsp [Neu5Acα/ß2-triazole-6-ßGalNAc]ThrArgProGlyOH 2. Despite interacting differently with SM3 monoclonal antibody, as shown by molecular dynamic simulations, this unnatural triazole glycopeptide may represent a promising candidate for cancer immunotherapy.


Assuntos
Antígenos Glicosídicos Associados a Tumores/química , Glicopeptídeos/química , Glicopeptídeos/síntese química , Mucina-1/química , Triazóis/química , Técnicas de Química Sintética
14.
J Alzheimers Dis ; 78(1): 353-370, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32986667

RESUMO

BACKGROUND: Alzheimer's disease (AD) is characterized by a progressive loss of episodic memory associated with amyloid-ß peptide aggregation and the abnormal phosphorylation of the tau protein, leading to the loss of cholinergic function. Acetylcholinesterase (AChE) inhibitors are the main class of drugs used in AD therapy. OBJECTIVE: The aim of the current study was to evaluate the potential of two tacrine-donepezil hybrid molecules (TA8Amino and TAHB3), which are AChE inhibitors, to induce neurodifferentiation and neuritogenesis in SH-SY5Y cells. METHODS: The experiments were carried out to characterize neurodifferentiation, cellular changes related to responses to oxidative stress and pathways of cell survival in response to drug treatments. RESULTS: The results indicated that the compounds did not present cytotoxic effects in SH-SY5Y or HepG2 cells. TA8Amino and TAHB3 induced neurodifferentiation and neuritogenesis in SH-SY5Y cells. These cells showed increased levels of intracellular and mitochondrial reactive oxygen species; the induction of oxidative stress was also demonstrated by an increase in SOD1 expression in TA8Amino and TAHB3-treated cells. Cells treated with the compounds showed an increase in PTEN(Ser380/Thr382/383) and AKT(Ser473) expression, suggesting the involvement of the AKT pathway. CONCLUSION: Our results demonstrated that TA8Amino and TAHB3 present advantages as potential drugs for AD therapy and that they are capable of inducing neurodifferentiation and neuritogenesis.


Assuntos
Inibidores da Colinesterase/uso terapêutico , Neurônios/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Donepezila/uso terapêutico , Humanos , Fármacos Neuroprotetores , Estresse Oxidativo/efeitos dos fármacos , PTEN Fosfo-Hidrolase , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas tau/metabolismo
16.
ChemMedChem ; 15(11): 933-948, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32314528

RESUMO

Anthracyclines are ranked among the most effective chemotherapeutics against cancer. They are glycoside drugs comprising the amino sugar daunosamine linked to a hydroxy anthraquinone aglycone, and act by DNA intercalation, oxidative stress generation and topoisomerase II poisoning. Regardless of their therapeutic value, multidrug resistance and severe cardiotoxicity are important limitations of anthracycline treatment that have prompted the discovery of novel analogues. This review covers the most clinically relevant anthracyclines and their development over decades, since the first discovered natural prototypes to recent semisynthetic and synthetic derivatives. These include registered drugs, drug candidates undergoing clinical trials, and compounds under pre-clinical investigation. The impact of the structural modifications on antitumour activity, toxicity and resistance profile is addressed.


Assuntos
Antraciclinas/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Animais , Antraciclinas/síntese química , Antraciclinas/química , Antineoplásicos/síntese química , Antineoplásicos/química , Humanos , Estrutura Molecular
17.
Molecules ; 25(8)2020 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-32325695

RESUMO

Losartan is widely used in clinics to treat cardiovascular related diseases by selectively blocking the angiotensin II type 1 receptors (AT1Rs), which regulate the renin-angiotensin system (RAS). Therefore, monitoring the physiological and pathological biodistribution of AT1R using positron emission tomography (PET) might be a valuable tool to assess the functionality of RAS. Herein, we describe the synthesis and characterization of two novel losartan derivatives PET tracers, [18F]fluoroethyl-losartan ([18F]FEtLos) and [18F]ammoniomethyltrifluoroborate-losartan ([18F]AMBF3Los). [18F]FEtLos was radiolabeled by 18F-fluoroalkylation of losartan potassium using the prosthetic group 2-[18F]fluoroethyl tosylate; whereas [18F]AMBF3Los was prepared following an one-step 18F-19F isotopic exchange reaction, in an overall yield of 2.7 ± 0.9% and 11 ± 4%, respectively, with high radiochemical purity (>95%). Binding competition assays in AT1R-expressing membranes showed that AMBF3Los presented an almost equivalent binding affinity (Ki 7.9 nM) as the cold reference Losartan (Ki 1.5 nM), unlike FEtLos (Ki 2000 nM). In vitro and in vivo assays showed that [18F]AMBF3Los displayed a good binding affinity for AT1R-overexpressing CHO cells and was able to specifically bind to renal AT1R. Hence, our data demonstrate [18F]AMBF3Los as a new tool for PET imaging of AT1R with possible applications for the diagnosis of cardiovascular, inflammatory and cancer diseases.


Assuntos
Radioisótopos de Flúor , Losartan/análogos & derivados , Losartan/química , Imagem Molecular , Receptor Tipo 1 de Angiotensina/química , Receptor Tipo 1 de Angiotensina/metabolismo , Animais , Camundongos , Modelos Animais , Imagem Molecular/métodos , Estrutura Molecular , Tomografia por Emissão de Pósitrons , Ligação Proteica , Compostos Radiofarmacêuticos , Distribuição Tecidual
18.
Future Med Chem ; 12(8): 689-708, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32193951

RESUMO

Aim: Glioblastoma multiforme (GBM) is an aggressive cancer with very limited clinical therapies. Herein, we have designed novel mercaptobenzimidazole derivatives (1-7) as multitarget antineoplastic drugs and assessed their antiproliferative profiles on an experimental model for GBM, the C6 glioma line. Results: The target compounds were synthesized in few steps with reasonable yields (33-90%). Compounds 1 (∼18 µM) and 4 (∼20 µM) showed dose-dependent antiproliferative effects on C6 glioma and significantly increased early apoptosis, but only 4 disrupted the cell cycle progression and did not induce autophagy. Docking simulations suggested these compounds as dual kinase and colchicine binding site inhibitors. Conclusion: In spite of the limited selective toxicity, 4 hold the potential to be further optimized for the treatment of GBM.


Assuntos
Antineoplásicos/farmacologia , Benzimidazóis/farmacologia , Desenho de Fármacos , Glioblastoma/tratamento farmacológico , Triazóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Benzimidazóis/síntese química , Benzimidazóis/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Simulação de Acoplamento Molecular , Triazóis/química , Células Tumorais Cultivadas
19.
Org Lett ; 22(5): 1991-1996, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32073274

RESUMO

We demonstrate that tuning the reactivity of Cu by the choice of oxidation state and counterion leads to the activation of both "armed" and "disarmed" type glycals toward direct glycosylation leading to the α-stereoselective synthesis of deoxyglycosides in good to excellent yields. Mechanistic studies show that CuI is essential for effective catalysis and stereocontrol and that the reaction proceeds through dual activation of both the enol ether as well as the OH nucleophile.


Assuntos
Cobre/química , Glicosídeos/síntese química , Catálise , Glicosídeos/química , Glicosilação , Estrutura Molecular , Oxirredução
20.
Pharmaceuticals (Basel) ; 12(3)2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31336868

RESUMO

N-substituted iminosugar analogues are potent inhibitors of glucosidases and glycosyltransferases with broad therapeutic applications, such as treatment of diabetes and Gaucher disease, immunosuppressive activities, and antibacterial and antiviral effects against HIV, HPV, hepatitis C, bovine diarrhea (BVDV), Ebola (EBOV) and Marburg viruses (MARV), influenza, Zika, and dengue virus. Based on our previous work on functionalized isomeric 1,5-dideoxy-1,5-imino-D-gulitol (L-gulo-piperidines, with inverted configuration at C-2 and C-5 in respect to glucose or deoxynojirimycin (DNJ)) and 1,6-dideoxy-1,6-imino-D-mannitol (D-manno-azepane derivatives) cores N-linked to different sites of glucopyranose units, we continue our studies on these alternative iminosugars bearing simple N-alkyl chains instead of glucose to understand if these easily accessed scaffolds could preserve the inhibition profile of the corresponding glucose-based N-alkyl derivatives as DNJ cores found in miglustat and miglitol drugs. Thus, a small library of iminosugars (14 compounds) displaying different stereochemistry, ring size, and N-substitutions was successfully synthesized from a common precursor, D-mannitol, by utilizing an SN2 aminocyclization reaction via two isomeric bis-epoxides. The evaluation of the prospective inhibitors on glucosidases revealed that merely D-gluco-piperidine (miglitol, 41a) and L-ido-azepane (41b) DNJ-derivatives bearing the N-hydroxylethyl group showed inhibition towards α-glucosidase with IC50 41 µM and 138 µM, respectively, using DNJ as reference (IC50 134 µM). On the other hand, ß-glucosidase inhibition was achieved for glucose-inverted configuration (C-2 and C-5) derivatives, as novel L-gulo-piperidine (27a) and D-manno-azepane (27b), preserving the N-butyl chain, with IC50 109 and 184 µM, respectively, comparable to miglustat with the same N-butyl substituent (40a, IC50 172 µM). Interestingly, the seven-membered ring L-ido-azepane (40b) displayed near twice the activity (IC50 80 µM) of the corresponding D-gluco-piperidine miglustat drug (40a). Furthermore, besides α-glucosidase inhibition, both miglitol (41a) and L-ido-azepane (41b) proved to be the strongest ß-glucosidase inhibitors of the series with IC50 of 4 µM.

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