5 research outputs found
Cytotoxicity and DNA damage in the neutrophils of patients with sickle cell anaemia treated with hydroxyurea
A hidroxiurĂ©ia (HU) constitui o avanço mais importante no tratamento da anemia falciforme (AF) por prevenir complicaçÔes e aumentar a qualidade de vida dos pacientes. Entretanto, alguns aspectos do tratamento com HU permanecem obscuros, incluindo a sua ação e potencial toxicidade em outras cĂ©lulas sanguĂneas, tais como neutrĂłfilos. Este estudo utilizou a mensuração da lactato desidrogenase (LDH) e do metil tiazoltetrazĂłlio (MTT) e o ensaio do cometa para investigar a citotoxicidade e Ăndice de dano (ID) ao DNA em neutrĂłfilos de pacientes com AF em uso do medicamento. Nos ensaios de LDH e MTT, observou-se alĂ©m de ausĂȘncia de toxicidade, uma ação citoprotetora no grupo de pacientes tratados, Grupo SSHU (n=21, 11 mulheres e 10 homens, com idades entre 19-63 anos), quando comparados aos pacientes sem tratamento, Grupo SS (n=20, 13 mulheres e 07 homens, 18-69 anos), e grupo de indivĂduos saudĂĄveis (AA) usado como controle (n=52, 28 mulheres e 24 homens, 19-60 anos), com redução significativa (pHydroxyurea (HU) is the most important advance in the treatment of sickle cell anaemia (SCA) for preventing complications and improving quality of life for patients. However, some aspects of treatment with HU remain unclear, including their effect on and potential toxicity to other blood cells such as neutrophils. This study used the measurement of Lactate Dehydrogenase (LDH) and Methyl ThiazolTetrazolium (MTT) and the comet assay to investigate the cytotoxicity and damage index (DI) of the DNA in the neutrophils of patients with SCA using HU.In the LDH and MTT assays, a cytoprotective effect was observed in the group of patients treated, as well as an absence of toxicity. When compared to patients without the treatment, the SS group (n=20, 13 women and 07 men, aged 18-69 years), and the group of healthy individuals (AA) used as a control group (n=52, 28 women and 24 men, aged 19-60 years), The SSHU group (n=21, 11 women and 10 men, aged 19-63 years) showed a significant reduction (
Cytotoxicity and DNA damage in the neutrophils of patients with sickle cell anaemia treated with hydroxyurea
Hydroxyurea (HU) is the most important advance in the treatment of sickle cell anaemia (SCA) for preventing complications and improving quality of life for patients. However, some aspects of treatment with HU remain unclear, including their effect on and potential toxicity to other blood cells such as neutrophils. This study used the measurement of Lactate Dehydrogenase (LDH) and Methyl ThiazolTetrazolium (MTT) and the comet assay to investigate the cytotoxicity and damage index (DI) of the DNA in the neutrophils of patients with SCA using HU.In the LDH and MTT assays, a cytoprotective effect was observed in the group of patients treated, as well as an absence of toxicity. When compared to patients without the treatment, the SS group (n=20, 13 women and 07 men, aged 18-69 years), and the group of healthy individuals (AA) used as a control group (n=52, 28 women and 24 men, aged 19-60 years), The SSHU group (n=21, 11 women and 10 men, aged 19-63 years) showed a significant reduction (p20 months), demonstrating that despite the cytoprotective effects in terms of cell viability, the use of HU can induce DNA damage in neutrophils
Estudo de citotoxicidade, inflamaĂĂo e estresse oxidativo em neutrĂfilos de pacientes com anemia falciforme: influĂncia do tratamento com hidroxiurĂia
Falciform Anemia (FA) is a hereditary hemoglobinopathy resulting from a β-globin gene mutation (α2β26 GLU→ VAL) that originates a hemoglobin variant called S (HbS). Its polymerization promotes hemolytic and vaso-occlusive crises (VOC). Nowadays it is known that these reactions are initial FA events that unleash a chain reaction that ends with the generation of oxygen reactive types (ORT) nitric oxide (NO) bioavailability reduction, endothelial lesion, susceptibility to infections and a chronic inflammatory process with direct involvement of neutrophils in the development of such mechanisms. Neutrophils of FA patients, besides developing more rigid, non-deformable structures, also show alterations in the expression of adhesion molecules and the production of cytokines and other mediators that may induce or aggravate clinical events observed in the disease. Hydroxyurea (HU) is the most important improvement in FA treatment and the only medicine with a strong impact on the patientsĂą quality of life, reducing the number of VOC, hospitalizations and deaths resulting from this condition. However, not much is known about the effects of this medicine on neutrophils and on the functionality of these cells. The present study aimed at investigating cytotoxicity, inflammation and oxidative stress markers in neutrophils of FA patients, as well as the effect of HU treatment over these parameters in hematology ambulatory patients from a university hospital and a blood center, both reference centers in Fortaleza Ăą CearĂ. The sample included 101 adult patients of both sexes diagnosed with FA through molecular study and it was divided into two groups: the SS Group Ăą composed of 47 FA patients and the SSHU Group Ăą composed of 54 FA patients under HU treatment. A control Group AA was composed of 50 healthy individuals, voluntary blood donors matched by age and sex. Neutrophils were isolated from whole blood by differential gradient and used to measure test. In toxicity tests carried out, it was observed that HU did not have any cytotoxic effect on patientsĂą neutrophils, however, was shown a cytoprotective action when compared to group AA and SS patients, with a significant reduction (p<0,001) in lactate dehydrogenase (LDH) levels and an increase in the percentage of viable cells through the metil tiazol tetrazolium (MTT) (p<0,001) and the Trypan Blue exclusion tests. Analyzing neutrophil involvement in inflammatory and oxidative stress processes and in FA, there was a significant elevation in the levels of cytokines and pro-inflammatory markers (TNF-α, MPO) and reduced antiinflammatory interleukin IL-10 group SS, as well as a significant decrease in the activity of antioxidant enzymes (SOD and GSH-Px). Patients under medical treatment with the tested medicine showed similar levels to those found in group AA. Oxidative damage were analyzed through malonaldehyde measurement (MDA), which was evidenced statistical differences between all studied groups (p<0,001), however with a higher average value in the non-treated group of patients. The present study ratified the important role of neutrophils in the inflammatory response promoted by the AF, and shown in an unprecedented way, with the Northeast-BR patients, treatment with HU did not reduce the viability of neutrophils, and modulates its mechanisms pro-inflammatory and pro -oxidants at levels comparable to those of healthy individuals.Anemia Falciforme (AF) Ă uma hemoglobinopatia hereditĂria resultante de uma mutaĂĂo pontual do gene da β-globina (α2β26 GLU→ VAL), originando a hemoglobina S (HbS), cuja polimerizaĂĂo promove crises hemolĂticas e vaso-oclusivas (CVO). Atualmente, sabe-se que as mesmas sĂo eventos iniciais na AF desencadeando uma cascata de reaĂĂes que culmina com geraĂĂo de espĂcies reativas de oxigĂnio, reduĂĂo da biodisponibilidade do Ăxido nĂtrico, lesĂo endotelial, susceptibilidade Ăs infecĂĂes e processo inflamatĂrio crĂnico, com envolvimento direto dos neutrĂfilos nesses mecanismos. Os neutrĂfilos de pacientes com AF exibem estruturas mais rĂgidas e indeformĂveis e alteraĂĂes na expressĂo de molĂculas de adesĂo e produĂĂo de citocinas e outros mediadores que podem induzir ou agravar as manifestaĂĂes clĂnicas da doenĂa. A hidroxiurĂia (HU) constitui o avanĂo mais importante no tratamento da AF, sendo o Ănico medicamento que, efetivamente, tem forte impacto na melhora da qualidade de vida dos pacientes, reduzindo o nĂmero de CVO, hospitalizaĂĂes e Ăbitos. No entanto, pouco se sabe sobre os efeitos deste medicamento sobre os neutrĂfilos e na funcionalidade dessas cĂlulas. O estudo teve como objetivo principal investigar a citotoxicidade, inflamaĂĂo e estresse oxidativo em neutrĂfilos de pacientes com AF, bem como o efeito do tratamento com HU sobre esses parĂmetros em pacientes atendidos pelos serviĂos ambulatoriais de hematologia de um hospital universitĂrio e de um hemocentro, ambos de referĂncia em Fortaleza-CearĂ. A amostra foi constituĂda por 101 pacientes adultos, de ambos os sexos, diagnosticados por estudo molecular, sendo divididos em dois grupos: Grupo SSĂą formado por 47 pacientes com AF, e, Grupo SSHUĂą formado por 54 pacientes em tratamento com HU. Um grupo controle, Grupo AA, foi formado por 50 indivĂduos saudĂveis, doadores voluntĂrios de sangue, com idade e sexo pareados. Os neutrĂfilos foram isolados do sangue total por diferenĂa de gradiente e utilizados para mensuraĂĂo dos testes. Nos ensaios de toxicidade, observou-se que a HU nĂo exerceu efeito citotĂxico nos neutrĂfilos dos pacientes, entretanto, foi evidenciado uma aĂĂo citoprotetora sobre os mesmos quando comparados aos pacientes SS e grupo AA, com uma reduĂĂo significativa (p<0,001) na atividade de lactato desidrogenase (LDH) e aumento no percentual de cĂlulas viĂveis pelo teste de exclusĂo por Azul de Tripan e ensaio do metil tiazol tetrazĂlio (MTT) (p<0,001). Analisando o envolvimento dos neutrĂfilos nos processos de inflamaĂĂo e estresse oxidativo na AF, constatou-se uma significativa elevaĂĂo nos nĂveis de citocinas e marcadores prĂ-inflamatĂrios (TNF-α, MPO) e uma reduĂĂo da interleucina anti-inflamatĂria IL-10 no grupo SS, bem como uma diminuiĂĂo significante da atividade das enzimas antioxidantes (SOD e GSH-Px). Os pacientes em terapia com HU apresentaram nĂveis semelhantes aos encontrados no grupo AA. Danos oxidativos foram analisados pela mensuraĂĂo do malonaldeĂdo (MDA), evidenciando diferenĂa estatĂstica entre todos os grupos do estudo (p<0,001), porĂm, com valor de mĂdia superior no grupo SS. O presente estudo ratificou o papel preponderante dos neutrĂfilos na resposta inflamatĂria promovida pela AF, e mostrou de maneira inĂdita, com pacientes do Nordeste-BR, que o tratamento com HU nĂo reduziu a viabilidade de neutrĂfilos, e modulou seus mecanismos prĂ-inflamatĂrios e prĂ-oxidantes a nĂveis comparĂveis aos de indivĂduos sadios
Cytotoxicity and DNA damage in the neutrophils of patients with sickle cell anaemia treated with hydroxyurea
Hydroxyurea (HU) is the most important advance in the treatment of sickle cell anaemia (SCA) for preventing complications and improving quality of life for patients. However, some aspects of treatment with HU remain unclear, including their effect on and potential toxicity to other blood cells such as neutrophils. This study used the measurement of Lactate Dehydrogenase (LDH) and Methyl ThiazolTetrazolium (MTT) and the comet assay to investigate the cytotoxicity and damage index (DI) of the DNA in the neutrophils of patients with SCA using HU.In the LDH and MTT assays, a cytoprotective effect was observed in the group of patients treated, as well as an absence of toxicity. When compared to patients without the treatment, the SS group (n=20, 13 women and 07 men, aged 18-69 years), and the group of healthy individuals (AA) used as a control group (n=52, 28 women and 24 men, aged 19-60 years), The SSHU group (n=21, 11 women and 10 men, aged 19-63 years) showed a significant reduction (p20 months), demonstrating that despite the cytoprotective effects in terms of cell viability, the use of HU can induce DNA damage in neutrophils