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1.
Lung ; 200(4): 495-503, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35816208

RESUMO

PURPOSE: To identify plasma alterations in lipid species in patients with chronic obstructive pulmonary disease (COPD), as well as, relationships with smoking status, oxidative and inflammatory markers. METHODS: Plasma was obtained from 100 patients with COPD and 120 healthy controls. Pulmonary function was assessed by plethysmography. Serum levels of IL-6 and TNF-α were determined by ELISA. Oxidative stress parameters were measured using standard methods. Lipids were extracted then analyzed by Matrix-Assisted Laser Desorption and Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF-TOF-MS). RESULTS: More than 40 lipid compounds were identified within plasma samples. Among these 19 lipid species including plasmalogens (PC O-), phosphatidylcholines (PC), and triglycerides (TG) were significantly altered in COPD. A decreased expression of PC O- (36:1, 36:2, 36:3, 36:4, 38:4, 38:5) species was found in patients with different severities compared to healthy controls. There was also a decrease in PC (34:3, 36:0, 36:4, 36:5, 40:6, 40:7) species in COPD patients. PC (34:3) levels were positively correlated with disease progression and pulmonary function decline (forced expiratory volume in 1 s (FEV1)) (r = 0.84, p < 0.001) and inversely correlated with thiobarbituric acid-reactive substances (TBARS) (r = - 0.77, p < 0.001). TG (50:0, 50:1, 52:1, 52:2, 52:3, 52:4, 54:4) species were altered in COPD patients and in those with advanced disease stages. Significant correlations between FEV1, TBARS, peroxynitrite, and TG (52:3) were found among COPD patients (r = - 0.69; r = 0.86; r = 0.77, p < 0.001, respectively). CONCLUSION: PC (34:3) and TG (52:3) could be potential lipid signatures of COPD that correlate with altered pulmonary function and oxidative status.


Assuntos
Fosfatidilcolinas , Doença Pulmonar Obstrutiva Crônica , Biomarcadores , Volume Expiratório Forçado , Humanos , Estresse Oxidativo , Índice de Gravidade de Doença , Substâncias Reativas com Ácido Tiobarbitúrico , Triglicerídeos
2.
Int J Environ Health Res ; 30(6): 630-642, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31081360

RESUMO

This study aimed to investigate the effect of red orange juice supplementation (ROJS) on performance, cardiovascular parameters, muscle damage and oxidative stress markers of athletes following exercise under polluted air. Eleven soccer players performed a Yo-Yo Intermittent Recovery Test Level-1 in polluted area (PA) and non-polluted area (NPA). Participants are invited to drink 500 ml of red orange or placebo (PLA) juice 2.5 h before the test. Blood samples were collected at rest and 3 min after each session to assess creatine kinase (CK), lactate dehydrogenase, malondialdehyde (MDA) and total antioxidant status. Our results showed that, VO2max, heart rate and systolic blood pressure post-exercise were significantly altered by pollution with both supplements, but the damage was lowered more with ROJS than PLA. Concerning muscle damage and oxidative stress markers, orange juice supplementation blunted the effect of pollution on CK levels post-exercise (p > 0.05) and decreases significantly (p < 0.05) the MDA levels post-exercise in PA and NPA compared to PLA supplementation. In conclusion, ROJS seemed to be an appropriate strategy to reduce the risk of exposure to pollution especially on muscle damage and oxidative stress markers.


Assuntos
Poluição do Ar/efeitos adversos , Desempenho Atlético , Fenômenos Fisiológicos Cardiovasculares , Citrus sinensis , Suplementos Nutricionais/análise , Sucos de Frutas e Vegetais/análise , Substâncias Protetoras/farmacologia , Atletas/estatística & dados numéricos , Biomarcadores/metabolismo , Fenômenos Fisiológicos Cardiovasculares/efeitos dos fármacos , Dieta , Humanos , Masculino , Músculos/efeitos dos fármacos , Músculos/fisiologia , Estresse Oxidativo , Substâncias Protetoras/análise , Futebol , Tunísia
3.
J Gene Med ; 20(1)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29165854

RESUMO

BACKGROUND: The present study aimed to examine the role of matrix metalloproteinase (MMP)-3 [(-1171) 5A/6A; Lys45Glu (A/G)], MMP-7 [(-181) A/G] and MMP-12 [(-82) A/G; Asn357Ser (A/G)] variants in the development and severity of chronic obstructive pulmonary disease (COPD) in Tunisians. METHODS: Plethysmography was performed in all participants to measure forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC parameters. Genotyping of MMP-3, MMP-7 and MMP-12 polymorphisms was carried out in 138 patients with COPD and 216 healthy controls using a polymerase chain reaction-restriction fragment length polymorphism. Serum levels of MMPs and cytokines (interleukin-6, tumor necrosis factor-α) were determined by an enzyme-linked immunosorbent assay. RESULTS: No significant correlations were observed between genetic variations in MMP-3, MMP-7 and MMP-12 and the risk of development of COPD. Additionally, no impact of MMP-7 (-181) A/G and MMP-12 [(-82) A/G; Asn357Ser (A/G)] polymorphisms was observed on the respective protein levels and clinical parameters of the disease. Interestingly, both MMP-3 (-1171) 5A/6A and Lys45Glu (A/G) variants were associated with respiratory function, as well as with serum levels of MMP-3 in COPD patients. A relationship was found between the (-1171) 6A and 45Glu (G) alleles of the MMP-3 gene and enhanced airflow limitation among COPD patients. Additionally, carriers of the 6A6A and 45 GG genotypes present higher MMP-3 levels than noncarriers. CONCLUSIONS: MMP-3 (-1171) 5A/6A and Lys45Glu (A/G) polymorphisms were associated with the decline of lung function among COPD patients. These results could be linked to the upregulation of MMP-3 in serum from COPD patients carrying the (-1171) 6A and 45 G homozygous genotypes.


Assuntos
Biomarcadores/sangue , Metaloproteinase 12 da Matriz/sangue , Metaloproteinase 3 da Matriz/sangue , Metaloproteinase 7 da Matriz/sangue , Polimorfismo de Nucleotídeo Único , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/genética , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Masculino , Metaloproteinase 12 da Matriz/genética , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 7 da Matriz/genética , Pessoa de Meia-Idade , Prognóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Índice de Gravidade de Doença , Tunísia/epidemiologia
4.
Mol Cell Biochem ; 445(1-2): 1-11, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29234928

RESUMO

This work focused on finding a relationship between acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities and the development and severity of COPD. The possible link of these enzymes to oxidative and inflammatory processes was also investigated. The study included 229 healthy controls and 153 COPD patients. Erythrocyte AChE and plasma BChE activities were determined using spectrophotometric methods. Markers related to the oxidative status including thiobarbituric acid-reactive substances (TBARS), total protein carbonyls (PCs), advanced oxidation protein products (AOPP), reduced glutathione, nitric oxide, and peroxynitrite were measured. We also evaluated the activity of glutathione peroxidase, catalase, and superoxide dismutase in the plasma and erythrocytes. Serum levels of IL-6 and TNF-α were measured by the enzyme-linked immunosorbent assay. COPD patients showed increased AChE and BChE activities in comparison to healthy controls. Interestingly, AChE activity was higher in COPD smokers than in nonsmokers, while no difference was revealed for BChE. In addition, our results showed an inverse correlation between AChE activity and the levels of IL-6 in COPD smokers. Positive correlations were found, in COPD smokers, between plasma BChE activity and the levels of several biomarkers of protein oxidative damage including AOPP and PC. Our findings suggest that the alterations in AChE and BChE activities may be related to the oxidative and inflammatory processes in COPD patients rendering these enzymes as markers of COPD disease.


Assuntos
Acetilcolinesterase/sangue , Biomarcadores/sangue , Butirilcolinesterase/sangue , Inflamação/sangue , Estresse Oxidativo , Doença Pulmonar Obstrutiva Crônica/enzimologia , Produtos da Oxidação Avançada de Proteínas/sangue , Estudos de Casos e Controles , Catalase/sangue , Eritrócitos/enzimologia , Feminino , Glutationa/sangue , Glutationa Peroxidase/sangue , Humanos , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/sangue , Ácido Peroxinitroso/sangue , Carbonilação Proteica , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fumar , Superóxido Dismutase/sangue , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fator de Necrose Tumoral alfa/sangue
5.
Cytokine ; 93: 66-73, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28526204

RESUMO

OBJECTIVE: The goal of this study was to examine the role of G894T (rs1799983), -786T/C (rs3918161) and a 27 bp variable number of tandem repeats (VNTR) 4B/4A of NOS3 gene on the risk and severity of COPD. METHODS: The study included 194 controls and 138 COPD patients. NOS3 G894T, -786T/C and 4B/4A variants were determined by PCR analysis based on the banding pattern on gel electrophoresis. Pulmonary function was evaluated using body plethysmography. The levels of nitric oxide, peroxynitrite and lipid peroxides (T-BARS) were determined using spectrophotometric methods. Levels of serum IL-6, TNF-α and TGFß were determined by ELISA. RESULTS: In case-control studies, both G894T and -786T/C variants were associated with COPD risk. A significantly increased risk of COPD was found with the NOS3894T and -786C alleles (OR:1.93, P=0.001; OR:2.05, P=0.001, respectively). No significant impact of the G894T and 4B/4A SNPs was found on COPD severity, while a significant correlation was retrieved between the NOS3 -786T/C variation and advanced stages (OR: 1.89, P=0.009). In addition, COPD patients with the -786CC genotype exhibited lower FEV1% values in comparison to -786TT carriers (48±3.28 vs. 58.06±2.3, P=0.01, respectively). Patients having the -786CC genotype presented lower plasma levels of nitric oxide and higher T-BARS in comparison to -786TT individuals (173.22±13.4 vs. 228.93±16.8, P=0.01; 1.8±0.15 vs. 1.22±0.15, P=0.01, respectively). CONCLUSION: This study provides the first evidence for the association of G894T, -786T/C variants with COPD risk among Tunisians. The -786T/C variation correlates with enhanced airflow limitation. This finding could be related to altered levels of nitric oxide and enhanced lipid peroxides among patients carrying the -786CC genotype.


Assuntos
Predisposição Genética para Doença , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico/sangue , Polimorfismo de Nucleotídeo Único , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/genética , Idoso , Feminino , Marcadores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Tunísia
6.
J Asthma ; 53(3): 227-37, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26516659

RESUMO

OBJECTIVE: This study aims to determine the systemic oxidant-antioxidant status in Tunisian patients with asthma. METHODS: We evaluated the levels of malondialdehyde (MDA) as thiobarbituric acid complexes, total protein carbonyls (PCs) and advanced oxidation protein products (AOPP). The levels of total thiols, protein sulfhydryls, glutathione (GSH), together with hydrogen peroxide, ascorbic acid, iron and total antioxidant status (TAS) were colorimetrically estimated. Glutathione peroxidase (GSH-Px), catalase (CAT) and superoxide dismutase (SOD) activities were assessed in plasma and erythrocytes by spectrophotometry. We also determined the levels of nitric oxide (NO) and peroxynitrite in plasma from asthmatic patients and healthy controls. The volume of fractionated exhaled NO (FeNO) was evaluated by the Medisoft HypAir method. Estimation of DNA damage was determined using the comet assay. RESULTS: Asthmatic patients showed increased levels of MDA in comparison to healthy controls (p < 0.001), while no significant difference was found in protein carbonyls (p = 0.79) and AOPP (p = 0.98). Patients with asthma also had significantly lower levels of total thiols (355.9 ± 15.72 versus 667.9 ± 22.65, p < 0.001), protein sulfhydryls (333.99 ± 16.41 versus 591.95 ± 24.28, p < 0.001) and glutathione (p < 0.001). They also showed decreased GSH-Px activity (p < 0.001), whereas no significant differences in measurements of catalase and SOD enzyme activities were observed between the two groups (respectively, p = 0.06 and p = 0.55). In addition, ascorbic acid and nitric oxide levels were decreased in asthmatics in comparison to controls (p < 0.01). CONCLUSIONS: Our findings highlight that oxidative stress and defective anti-oxidative status are major alterations in Tunisian patients with asthma.


Assuntos
Asma/fisiopatologia , Adulto , Produtos da Oxidação Avançada de Proteínas/metabolismo , Ácido Ascórbico/metabolismo , Asma/sangue , Biomarcadores , Catalase/metabolismo , Feminino , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Masculino , Malondialdeído/metabolismo , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Estresse Oxidativo/fisiologia , Carbonilação Proteica/fisiologia , Testes de Função Respiratória , Índice de Gravidade de Doença , Superóxido Dismutase/metabolismo , Tunísia
7.
Cells ; 11(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36497088

RESUMO

Uveal melanoma (UM) is the most common primary intraocular tumor and often spreads to the liver. Intercellular communication though extracellular vesicles (EVs) plays an important role in several oncogenic processes, including metastasis, therapeutic resistance, and immune escape. This study examines how EVs released by UM cells modify stellate and endothelial cells in the tumor microenvironment. The surface markers, and the concentration and size of EVs derived from UM cells or choroidal melanocytes were characterized by high-resolution flow cytometry, electron microscopy, and Western blotting. The selective biodistribution of EVs was studied in mice by fluorescence imaging. The activation/contractility of stellate cells and the tubular organization of endothelial cells after exposure to melanomic EVs were determined by traction force microscopy, collagen gel contraction, or endothelial tube formation assays. We showed that large EVs from UM cells and healthy melanocytes are heterogenous in size, as well as their expression of phosphatidylserine, tetraspanins, and Tsg101. Melanomic EVs mainly accumulated in the liver and lungs of mice. Hepatic stellate cells with internalized melanomic EVs had increased contractility, whereas EV-treated endothelial cells developed more capillary-like networks. Our study demonstrates that the transfer of EVs from UM cells leads to a pro-fibrotic and pro-angiogenic phenotype in hepatic stellate and endothelial cells.


Assuntos
Vesículas Extracelulares , Melanoma , Camundongos , Animais , Microambiente Tumoral , Células Endoteliais , Distribuição Tecidual , Vesículas Extracelulares/metabolismo , Melanoma/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-33545665

RESUMO

We hypothesized that polymorphisms of genes involved in the prostaglandin pathway could be associated with COPD. In this study we explored the involvement of genetic polymorphisms in PTGS2, PTGER2 and PTGER4 genes in the development and severity of COPD and their effects on plasma concentrations of inflammatory/oxidative stress markers. We identified genotypes of PTGS2, PTGER2 and PTGER4 SNPs in a Tunisian cohort including COPD patients (n = 138) and control subjects (n = 216) using PCR-RFLP and PCR TaqMan. Pulmonary function (FEV1 and FVC) were assessed by plethsmography. PGE2, PGD2 and cytokine plasma (IL-6, IL-18, TNF-α, TGF-ß) concentrations were measured using ELISA and colorimetric standard methods were used to determine oxidative stress concentrations. Genotype frequencies of rs2745557 in PTGS2 and rs2075797 in PTGER2 were different between COPD cases and controls. There was no correlation between these polymorphisms and lung function parameters. For rs2745557, the A allele frequency was higher in COPD cases than in controls. For rs2075797, carriers of the GG genotype were more frequent in the COPD group than in controls. Only rs2745557 in PTGS2 had an effect on PGD2 and cytokine plasma concentrations. PGD2 was significantly decreased in COPD patients with the GA or AA genotypes. In contrast, IL-18 and NO plasma concentrations were increased in COPD rs2745557 A allele carriers as compared to homozygous GG subjects. Our findings suggest that rs2745557 in PTGS2 and rs2075797 in PTGER2 are associated with COPD development but not with its severity.


Assuntos
Ciclo-Oxigenase 2/genética , Polimorfismo de Nucleotídeo Único , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/genética , Receptores de Prostaglandina E Subtipo EP2/genética , Idoso , Alelos , Estudos de Casos e Controles , Estudos de Coortes , Citocinas/sangue , Dinoprostona/sangue , Feminino , Frequência do Gene , Predisposição Genética para Doença/genética , Humanos , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Prostaglandina D2/sangue , Doença Pulmonar Obstrutiva Crônica/sangue , Receptores de Prostaglandina E Subtipo EP4/genética , Fatores de Risco , Tunísia/epidemiologia
9.
Free Radic Res ; 53(3): 293-303, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30668180

RESUMO

Chronic obstructive pulmonary disease (COPD) is a major cause of mortality that has been associated with inflammation and oxidative stress. The purpose of the present case-control study was to determine the relationships between oxidative stress-related genetic variants and the risk and severity of COPD, as well as, the influence of these variants on inflammatory and oxidative stress parameters. Genotyping of superoxide dismutase 1 (SOD1) + 35 A/C (rs2234694), catalase [A-21T (rs7943316), C-262T (rs1001179)] and glutathione peroxidase 1 (reduced glutathione (GSH)-Px1) 198Pro/Leu (rs1050450) was carried out in 143 patients with COPD and 216 healthy controls using PCR-RFLP. Serum levels of IL-6 and TNF-α were determined by enzyme-linked immunosorbent assays (ELISA), while the levels of reduced GSH, total antioxidant status (TAS), H2O2, lipid peroxides (TBARS) and protein carbonyls (PCs) were determined using spectrophotometric methods. We also evaluated the activities of GSH-Px, catalase, and superoxide dismutase (SOD) in both plasma and erythrocytes. We did not observe significant differences in the genotype and allele frequencies of chosen variants between COPD patients and healthy controls. A significant correlation was retrieved between the SOD1 + 35A/C variant and disease severity (odds ratios (OR) = 0.15, p = 0.04). In addition, patients having the +35AC genotype presented increased plasma levels of GSH and a reduced level of PCs (p = 0.03, p = 0.04, respectively). The present data highlighted the important role of antioxidant enzymes and their genetic variants in the oxidative stress-mediated pathogenesis and progression of COPD.


Assuntos
Catalase/metabolismo , Variação Genética/genética , Glutationa/metabolismo , Carbonilação Proteica/imunologia , Doença Pulmonar Obstrutiva Crônica/genética , Superóxido Dismutase-1/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Doença Pulmonar Obstrutiva Crônica/patologia , Superóxido Dismutase-1/genética , Tunísia
10.
Biol Trace Elem Res ; 161(1): 20-31, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25074430

RESUMO

This study was aimed to evaluate the oxidant-antioxidant imbalance in the pathogenesis of chronic obstructive pulmonary disease (COPD) in Tunisians. We assessed 16 parameters related to the oxidative status that include malondialdehyde (MDA), total protein carbonyls (PCs), and advanced oxidation protein products (AOPP). We also examined the activity of glutathione peroxydase (GSH-Px), catalase, and superoxide dismutase (SOD) in the plasma and erythrocytes. Levels of total thiols, reduced glutathione (GSH), total antioxidant status (TAS), hydrogen peroxide, ascorbic acid, iron, and protein sulfhydryls were determined using spectrophotometry. We also evaluated the level of nitric oxide (NO) and peroxynitrite in plasma from COPD patients and healthy controls. Estimation of DNA damage was determined using the comet assay. Pulmonary functional tests were performed by body plethysmography. Levels of MDA, PC, DNA damage, and AOPP were significantly increased while total thiols, GSH, and TAS were decreased in COPD patients. GSH-Px activity was higher in COPD patients while no difference was found for catalase and SOD. We also observed a lower level of NO and peroxynitrite in COPD patients. Decreased levels of peroxynitrite were found to correlate with disease progression, as well as with forced expiratory volume in 1 s/forced vital capacity among COPD patients. Multivariate analysis revealed that NO is associated with pathological pathways that help to predict patient outcome independently of the degree of airflow obstruction. These results indicate the presence of a systemic oxidative stress and highlight the importance of NO and peroxynitrite as major effectors in COPD development and airflow obstruction.


Assuntos
Óxido Nítrico/sangue , Estresse Oxidativo , Ácido Peroxinitroso/sangue , Doença Pulmonar Obstrutiva Crônica/sangue , Adulto , Produtos da Oxidação Avançada de Proteínas/sangue , Idoso , Catalase/sangue , Ensaio Cometa , Dano ao DNA , Volume Expiratório Forçado , Glutationa/sangue , Glutationa Peroxidase/sangue , Humanos , Malondialdeído/sangue , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/patologia , Índice de Gravidade de Doença , Superóxido Dismutase/sangue , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Tunísia
11.
Ann Biol Clin (Paris) ; 70(5): 553-65, 2012 Oct 01.
Artigo em Francês | MEDLINE | ID: mdl-23047902

RESUMO

Breast cancer represents a major public health problem. Approximately one woman in ten is likely to develop a malignant tumor of the breast in their lifetime. The frequency of breast cancer is rising steadily for 20 years and the practical benefits in the diagnosis, prognosis and treatment of this disease are still too limited. Actually, there is no tumor marker with a specificity and sensitivity sufficient to have an utility in clinical and early diagnosis of breast cancer, although, carcinoembryonic antigen (CEA), MUC-1 and CA 15-3 were reported to be useful as markers for monitoring this disease. Thus, proteomics approaches are needed for the discovery and the identification of new protein biomarkers that may allow a better understanding of biological mechanisms of breast tumor development and serve as potential therapeutic targets. This article reviews advances in this field, as well as, the major contribution of these markers in breast pathology, with a focus on their biological characteristics and their clinical and therapeutic involvement.


Assuntos
Neoplasias da Mama/etiologia , Carcinoma/etiologia , Conhecimento , Proteômica/métodos , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Pesquisa Biomédica/métodos , Pesquisa Biomédica/tendências , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/metabolismo , Carcinoma/diagnóstico , Carcinoma/metabolismo , Feminino , Humanos , Oncologia/tendências , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/metabolismo , Proteoma/análise , Proteoma/metabolismo
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