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2.
Cureus ; 15(8): e43718, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37724235

RESUMO

Introduction Wilson's disease (WD) is a rare and underdiagnosed genetic disorder caused by anomalous tissue copper deposition, and for which epidemiological studies, specifically in Portugal, are scarce. Objectives This study aimed to evaluate the prevalence and incidence of WD and provide a description of its main clinical and laboratory features. Methods A retrospective study was carried out, with a search between 1995 and 2015, of all patients with a minimum follow-up of three months and birth confirmed in the northern region of Portugal, with an estimated population of 3,689,682 inhabitants. Database collection was based on the Portuguese National Health Service's clinical coding system, relying on clinical data from 13 northern Portuguese hospitals, liver biopsy histology results, and hospital prescription records. Clinical and biochemical correlations were statistically assessed using chi-square, Mann-Whitney U, Friedman, and Wilcoxon tests. Results Over the 20-year period, a prevalence of 1:37.000 and an incidence of one per million person-year was found. A total of 94 patients were analyzed, with a slight male predominance (53%), the majority with the onset of clinical manifestations in pediatric age (56%), with a median age at diagnosis of 16.6 years (interquartile range of 12.3-20,.8 years). Most patients presented with predominant liver disease (54.8%), with more than a third with cirrhosis; mixed hepatic and neurological manifestations in 17.9%; and mainly neurological symptoms in 10.7% of the patients. Neurological impairment was strongly associated with delayed development of the manifestations of the disease (p = 0.001) and also a higher detection of Kayser-Fleischer rings (p < 0.001), present in 27.0% of the patients. Regarding therapy, penicillamine has been the most widely used, with adverse reactions reported in 24.8%. At six and 12 months after initiation of therapy, a significant decrease in liver enzymes was found (ALT: p = 0.002; AST: p = 0.002, respectively), but no significant reduction was observed in urinary copper excretion. Conclusion This was one of the first studies regarding WD prevalence in a Portuguese population, contributing to a better understanding of the epidemiology, diagnosis, and management of WD in the northern region of Portugal. WD should be considered in any individual with unexplained hepatic or neurological manifestations, and initial symptoms may manifest at an early age, even in children less than five years old. A high percentage of patients were identified in the early stages of the disease by asymptomatic elevation of transaminases. Following copper chelation therapy, cytolysis markers appear to be more sensitive indicators of treatment response.

3.
Chem Commun (Camb) ; 59(47): 7240-7242, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37222285

RESUMO

We herein describe the cell-specific release of alcohol-containing payloads via a sulfatase-sensitive linker in antibody-drug conjugates (ADCs). The linker shows efficient sulfatase-mediated release and high stability in human and mouse plasma. In vitro evaluation demonstrates potent antigen dependent toxicity towards breast cancer cell lines.


Assuntos
Antineoplásicos , Imunoconjugados , Animais , Camundongos , Humanos , Imunoconjugados/farmacologia , Etanol , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
4.
Sci Rep ; 11(1): 13297, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34168259

RESUMO

Pancreatic cancer stem cells (PCSCs) play a key role in the aggressiveness of pancreatic ductal adenocarcinomas (PDAC); however, little is known about their signaling and metabolic pathways. Here we show that PCSCs have specific and common proteome and lipidome modulations. PCSCs displayed downregulation of lactate dehydrogenase A chain, and upregulation of trifunctional enzyme subunit alpha. The upregulated proteins of PCSCs are mainly involved in fatty acid (FA) elongation and biosynthesis of unsaturated FAs. Accordingly, lipidomics reveals an increase in long and very long-chain unsaturated FAs, which are products of fatty acid elongase-5 predicted as a key gene. Moreover, lipidomics showed the induction in PCSCs of molecular species of cardiolipin with mixed incorporation of 16:0, 18:1, and 18:2 acyl chains. Our data indicate a crucial role of FA elongation and alteration in cardiolipin acyl chain composition in PCSCs, representing attractive therapeutic targets in PDAC.


Assuntos
Carcinoma Ductal Pancreático/metabolismo , Cardiolipinas/metabolismo , Subunidade alfa da Proteína Mitocondrial Trifuncional/metabolismo , Células-Tronco Neoplásicas/metabolismo , Neoplasias Pancreáticas/metabolismo , Humanos , Metabolismo dos Lipídeos , Lipidômica , Proteômica , Regulação para Cima
5.
Free Radic Biol Med ; 144: 223-233, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31173844

RESUMO

Pyruvate kinase catalyses the last step in glycolysis and has been suggested to contribute to the regulation of aerobic glycolysis in cancer cells. It can be inhibited by oxidation of cysteine residues in vitro and in vivo, which is relevant to the more pro-oxidant state in cancer and proliferating tissues. These conditions also favour lipid peroxidation and the formation of electrophilic fragmentation products, including short-chain aldehydes that can covalently modify proteins. However, as yet few studies have investigated their interactions with pyruvate kinase, so we investigated the effects of three different aldehydes, acrolein, malondialdehyde and 4-hydroxy-2(E)-hexenal (HHE), on the structure and activity of the enzyme. Analysis by LC-MS/MS showed unique modification profiles for each aldehyde, but Cys152, Cys423 and Cys474 were the residues most susceptible to electrophilic modification. Analysis of enzymatic activity under these conditions showed that acrolein was the strongest inhibitor, and at incubation times longer than 2 h, pathophysiological concentrations induced significant effects. Treatment of MCF-7 cells with the aldehydes caused similar losses of pyruvate kinase activity to those observed in vitro, and at lower concentrations than those required to cause cell death, with time and dose-dependent effects; acrolein adducts on Cys152 and Cys358 were detected. Cys358 and Cys474 are located at or near the allosteric or active sites, and formation of adducts on these residues probably contributes to loss of activity at low treatment concentrations. This study provides the first detailed analysis of the structure-activity relationship of C3 and C6 aldehydes with pyruvate kinase, and suggests that reactive short-chain aldehydes generated in diseases with an oxidative aetiology or from environmental exposure such as smoking could be involved in the metabolic alterations observed in cancer cells, through alteration of pyruvate kinase activity.


Assuntos
Acroleína/farmacologia , Aldeídos/farmacologia , Cisteína/química , Malondialdeído/farmacologia , Piruvato Quinase/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Biocatálise/efeitos dos fármacos , Cromatografia Líquida , Cisteína/metabolismo , Relação Dose-Resposta a Droga , Ensaios Enzimáticos , Humanos , Cinética , Peroxidação de Lipídeos , Células MCF-7 , Músculo Esquelético/química , Músculo Esquelético/enzimologia , Piruvato Quinase/isolamento & purificação , Piruvato Quinase/metabolismo , Coelhos , Relação Estrutura-Atividade , Espectrometria de Massas em Tandem
6.
Arch Biochem Biophys ; 646: 38-45, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29580947

RESUMO

Lipids containing polyunsaturated fatty acids are primary targets of oxidation, which produces reactive short-chain aldehydes that can covalently modify proteins, a process called lipoxidation. Improved mass spectrometry (MS) methods for the analysis of these adducts in complex biological systems are needed. Lysozyme and human serum albumin (HSA) were used as model proteins to investigate lipoxidation products formed by two short-chain aldehydes, acrolein and pentanal, which are unsaturated and saturated aldehydes respectively. The adducts formed were stabilized by NaBH4 or NaBH3CN reduction and analysed by MS. Analysis of intact modified lysozyme showed a pentanal modification resulting from Schiff's base formation (+70 Da), and up to 8 acrolein adducts, all resulting from Michael addition (+58 Da). Analysis of tryptic digests identified specific histidine, cysteine and lysine residues modified in both lysozyme and HSA, and determined characteristic amino acid-specific fragmentations. Eight different internal fragment ions were found that could be used as general diagnostic ions for pentanal- and acrolein-modified amino acids. The combined use of intact protein analysis and LC-MS/MS methods provided a powerful tool for the identification and localization of aldehyde-protein adducts, and the diagnostic ions will facilitate the development of targeted MS methods for analysis of adducts in more complex samples.


Assuntos
Acroleína/química , Aldeídos/química , Muramidase/química , Fragmentos de Peptídeos/química , Albumina Sérica Humana/química , Cromatografia Líquida/métodos , Cisteína/química , Histidina/química , Humanos , Lisina/química , Oxirredução , Espectrometria de Massas em Tandem/métodos
7.
Eur J Med Chem ; 121: 331-337, 2016 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-27267003

RESUMO

Cinnamylideneacetophenones (CA) are an important group of α,ß,γ,δ-diunsaturated ketones that have been widely used in a variety of synthetic transformations. Biological studies concerning these compounds are scarce and refer mainly to antiviral and antibacterial evaluations. Curcumin (CR), a natural polyphenol, is a yellow pigment extracted from the plant Curcuma longa, which is one of the major spices used in the Indian culinary. It has been reported that CR has cancer chemopreventive properties in a range of animal models of chemical carcinogenesis, along with antioxidative and anti-inflammatory properties. Inspired by the biological activity shown by CR and their structural resemblance with CA, it was considered to study the ability of the latter molecules to inhibit lipid oxidation induced by the hydroxyl radical (Fenton reaction) by electrospray ionization (ESI) mass spectrometry (MS) using phosphatidylcholine (PC) liposomes as a model of cell membrane. Compound 4, holding a methylated hydroxy group in the position R(2), and CR showed similar effects in inhibiting lipid peroxidation. In the presence of 7, the extension of oxidation was higher than the one verified in all other compounds. Other methodologies, namely DPPH radical scavenging and oxygen radical absorption capacity (ORAC) assays, were performed to complement and clarify the results attained by oxidation of PC monitored by ESI-MS and to evaluate the antioxidant profile of compounds. For both assays, compound 7 showed to be rather efficient due to its specific structure. This derivative can form a quite stable allylic radical by abstraction of a hydrogen atom which accounts for these results.


Assuntos
Acetofenonas/química , Acetofenonas/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Fosfatidilcolinas/metabolismo , Peróxido de Hidrogênio/química , Ferro/química , Oxirredução/efeitos dos fármacos
8.
J Cell Physiol ; 231(5): 1024-32, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26363509

RESUMO

Mesenchymal stromal cells (MSCs) present anti-inflammatory properties and are being used with great success as treatment for inflammatory and autoimmune diseases. In clinical applications MSCs are subjected to a strong pro-inflammatory environment, essential to their immunosuppressive action. Despite the wide clinical use of these cells, how MSCs exert their effect remains unclear. Several lipids are known to be involved in cell's signaling and modulation of cellular functions. The aim of this paper is to examine the variation in lipid profile of MSCs under pro-inflammatory environment, induced by the presence of tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ), using the most modern lipidomic approach. Major changes in lipid molecular profile of phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS), lysoPC (LPC), and sphingomyelin (SM) classes were found. No changes were observed in the phosphatidylinositol (PI) profile. The levels of PC species with shorter fatty acids (FAs), mainly C16:0, decreased under pro-inflammatory stimuli. The level of PC(40:6) also decreased, which may be correlated with enhanced levels of LPC(18:0), which is known to be an anti-inflammatory LPC, observed in MSCs subjected to TNF-α and IFN-γ. Simultaneously, the relative amounts of PC(36:1) and PC(38:4) increased. TNF-α and IFN-γ also enhanced the levels of PE(40:6) and decreased the levels of PE(O-38:6). Higher expression of PS(36:1) and SM(34:0) along with a decrease in PS(38:6) levels were observed. These results indicate that lipid metabolism and signaling are modulated during MSCs activation, which suggests that lipids may be involved in MSCs functional and anti-inflammatory activities.


Assuntos
Citocinas/farmacologia , Mediadores da Inflamação/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Metabolômica , Fosfolipídeos/metabolismo , Adulto , Células Cultivadas , Cromatografia em Camada Fina , Ácidos Graxos/metabolismo , Humanos , Interferon gama/farmacologia , Espectrometria de Massas , Células-Tronco Mesenquimais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Adulto Jovem
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