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1.
J Clin Med ; 12(22)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38002579

RESUMO

Patients with end-stage chronic kidney disease show higher systemic oxidative stress and exhale more hydrogen peroxide (H2O2) than healthy controls. Kidney transplantation reduces oxidative stress and H2O2 production by blood polymorphonuclear leukocytes (PMNs). Kidney transplant recipients (KTRs) may be predisposed to an impairment of lung diffusing capacity due to chronic inflammation. Lung function and H2O2 concentration in the exhaled breath condensate (EBC) were compared in 20 KTRs with stable allograft function to 20 healthy matched controls. Serum interleukin eight (IL-8) and C-reactive protein (CRP), blood cell counts, and spirometry parameters did not differ between groups. However, KTRs showed lower total lung diffusing capacity for carbon monoxide, corrected for hemoglobin concentration (TLCOc), in comparison to healthy controls (92.1 ± 11.5% vs. 102.3 ± 11.9% of predicted, p = 0.009), but similar EBC H2O2 concentration (1.63 ± 0.52 vs. 1.77 ± 0.50 µmol/L, p = 0.30). The modality of pre-transplant renal replacement therapy had no effect on TLCOc and EBC H2O2. TLCOc did not correlate with time after transplantation. In this study, TLCOc was less reduced in KTRs in comparison to previous reports. We suggest this fact and the non-elevated H2O2 exhalation exhibited by KTRs, may result perhaps from the evolution of the immunosuppressive therapy.

2.
Nutrients ; 14(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35956359

RESUMO

Carotenoids are organic, liposoluble pigments found in nature, which are responsible for the characteristic colors of ripe tomatoes, carrots, peppers, and crustaceans, among others. Palliative care provided to patients with an incurable disease is aimed at improving the patient's quality of life through appropriate treatment of symptoms accompanying the disease. Palliative care patients with burdensome symptoms related to advanced-stage cancers are especially interested in the use of natural dietary supplements and herbal remedies to reduce symptoms' intensity and ameliorate the quality of life. Carotenoids seem to be a group of natural compounds with particularly promising properties in relieving symptoms, mainly due to their strong antioxidant, anti-inflammatory, and neuroprotective properties. Moreover, carotenoids have been used in folk medicine to treat various diseases and alleviate the accompanying symptoms. In this narrative review, the authors decided to determine whether there is any scientific evidence supporting the rationale for carotenoid supplementation in advanced-stage cancer patients, with particular emphasis on the adjuvant treatment of cancer-related symptoms, such as neuropathic pain and cancer-related cachexia.


Assuntos
Carotenoides , Neoplasias , Antioxidantes/uso terapêutico , Carotenoides/uso terapêutico , Suplementos Nutricionais , Humanos , Neoplasias/complicações , Neoplasias/terapia , Cuidados Paliativos , Qualidade de Vida
3.
Nutrients ; 13(3)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673687

RESUMO

Hemodialysis (HD) is the most common method of renal replacement therapy. Besides toxins, it eliminates nutrients from the circulation, such as ascorbic acid (AA). HD-patients present AA deficiency more often than representatives of the general population, also due to dietary restrictions. This condition aggravates oxidative stress and inflammation related to uremia and extracorporeal circulation and increases cardiovascular risk followed by mortality. Supplementation of AA seems to be a promising approach in the treatment of hemodialysis patients. Many successful interventions restored plasma AA concentration in HD patients by enteral or intravenous supplementation, concomitantly inhibiting oxidative stress and inflammation. A significant number of studies reported opposite, serious pro-oxidant effects of AA. In this narrative review, we present studies, commenting on their limitations; on AA plasma or serum concentration and the influence of its supplementation on protein and lipid peroxidation, DNA damage, reactive oxygen species generation, paraoxonase activity, advanced glycation endproducts, and C-reactive protein (CRP) concentration. Moreover, in terms of safety, the possible development of oxalosis in HD patients regarding the intravenous or enteral route of AA administration is discussed. Unequivocal clinical results of recent studies on hemodialysis patients are displayed.


Assuntos
Ácido Ascórbico/farmacologia , Inflamação , Estresse Oxidativo , Diálise Renal , Vitaminas/farmacologia , Ácido Ascórbico/administração & dosagem , Humanos , Vitaminas/administração & dosagem
4.
Nutrients ; 13(3)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652579

RESUMO

High-dose intravenously administered vitamin C (IVC) is widely used in cancer patients by complementary and alternative medicine practitioners. The most frequent indications for IVC therapy result from the belief in its effectiveness as a potent anti-cancer agent which additionally enhances chemosensitivity of cancer cells and reduces chemotherapy-related toxicities and fatigue intensity. In this narrative review, we decided to deal with this issue, trying to answer the question whether there is any scientific evidence supporting the rationale for application of high-dose IVC therapy in advanced-stage cancer patients. Although results obtained from preclinical studies demonstrated that millimolar ascorbate plasma concentrations achievable only after IVC administration were cytotoxic to fast-growing malignant cells and inhibited tumor growth as well as prolonged the survival of laboratory animals, such positive effects were not found in human studies with advanced-stage cancer patients. We also have not found the rationale for the use of IVC to increase the effectiveness of chemotherapy and to reduce the chemotherapy-induced toxicity in the above mentioned group. Nevertheless, in palliative care, high-dose IVC might be considered as a therapy improving the quality of life and reducing cancer-related symptoms, such as fatigue and bone pain. However, because of the absence of placebo-controlled randomized trials on IVC efficacy in advanced-stage cancer patients, the placebo effect cannot be excluded.


Assuntos
Antineoplásicos/administração & dosagem , Ácido Ascórbico/administração & dosagem , Neoplasias/tratamento farmacológico , Cuidados Paliativos/métodos , Administração Intravenosa , Animais , Dor do Câncer/tratamento farmacológico , Dor do Câncer/etiologia , Fadiga/tratamento farmacológico , Fadiga/etiologia , Humanos , Neoplasias/complicações , Resultado do Tratamento
5.
Ther Apher Dial ; 21(6): 572-585, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29024501

RESUMO

Plant phenols may accumulate in end-stage kidney disease. The effect of hemodialysis on their plasma concentration remains poorly determined. Contingent on concentration, health-promoting or noxious effects occur; therefore, we assessed plasma concentration in hemodialyzed patients. In total, 21 maintenance hemodialyzed patients with diuresis < 500 mL per day (with oliguria), nine hemodialyzed patients with diuresis ≥ 500 mL per day (without oliguria) and 31 healthy volunteers were included. Nine phenolic acids were identified with high-performance liquid chromatography and total polyphenol concentration was determined with the Folin-Ciocalteu method in pre- or post-hemodialysis plasma and pre- or intra-hemodialysis dialysate. The concentration of total polyphenols was 27% higher in pre-hemodialysis plasma than in that of controls (0.95 ± 0.18 mmol/L [P < 0.0001]). The concentration of total polyphenols was higher in patients with oliguria (1.01 ± 0.17) than in those without (0.84 ± 0.13 mmol/L), despite the former having more intense hemodialysis (Kt/V 1.29 ± 0.31 and 0.77 ± 0.25, respectively). Pre-hemodialysis phenolic acid concentration in patients undergoing dialysis exceeded reference values by 3 to 34 times (3-hydroxyphenylacetic acid and vanillic acid, respectively), from 0.69 (dihydrocaffeic acid) to 169.3 µmol/L (hippuric acid). The concentration of six phenolic acids (3-hydroxyhippuric, caffeic, dihydrocaffeic, hippuric, homovanillic, and vanillic acid) was 1.1 (homovanillic) to 11.3 (3-hydroxyhippuric) times higher in patients with oliguria than in those without. 4-hydroxyhippuric acid occurred more in the plasma of patients with oliguria than in those without oliguria. A single hemodialysis session decreased total polyphenol concentration by 16% and phenolic acids from 30% (caffeic) to 58% (vanillic and 3-hydroxyphenylacetic acid) and these compounds appeared in the dialysate. The percentage decrease (Δ%) of creatinine concentration correlated with the Δ% of total polyphenols and five phenolic acids (3-hydroxyphenylacetic, dihydrocaffeic, hippuric, homovanillic, and vanillic acid). Urea Δ% and Kt/V correlated only with the Δ% of homovanilic acid. The results demonstrate that phenols accumulate variably in hemodialyzed patients and are differently eliminated during hemodialysis. Residual renal function ensures a lower concentration of plasma phenols.


Assuntos
Hidroxibenzoatos/sangue , Falência Renal Crônica/terapia , Fenóis/sangue , Diálise Renal/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Cromatografia Líquida de Alta Pressão , Creatinina/metabolismo , Soluções para Diálise/química , Feminino , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Oligúria/terapia
6.
Redox Rep ; 22(6): 308-314, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27611345

RESUMO

OBJECTIVES: Reactive oxygen species, which are implicated in the process of carcinogenesis, are also responsible for cell death during chemotherapy (CHT). Therefore, the aim of the study was to evaluate exhaled H2O2 levels in non-small cell lung cancer (NSCLC) patients before and after CHT. METHODS: Thirty patients (age 61.3 ± 9.3 years) with advanced NSCLC (stage IIIB-IV) and 15 age-matched healthy cigarette smokers were enrolled into the study. Patients received four cycles of cisplatin or carboplatin with vinorelbine every three weeks. Before and after the first, second, and fourth cycle, the concentration of H2O2 in exhaled breath condensate was measured with respect to treatment response. RESULTS: At the baseline, NSCLC patients exhaled 3.8 times more H2O2 than the control group (0.49 ± 0.14 vs. 0.13 ± 0.03 µmol/L, P < 0.05); this difference persisted throughout the study. CHT had no noticeable effect on exhaled H2O2 levels independent of the treatment response (partial remission vs. progressive disease). Pre- and post-CHT cycles of H2O2 levels generally correlated positively. DISCUSSION: The study demonstrated the occurrence of oxidative stress in the airways of advanced NSCLC patients. Exhaled H2O2 level was not affected by CHT and independent of treatment results and changes in the number of circulating neutrophils.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Peróxido de Hidrogênio/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Corticosteroides/uso terapêutico , Idoso , Carboplatina/uso terapêutico , Cisplatino/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espécies Reativas de Oxigênio/metabolismo , Antagonistas do Receptor 5-HT3 de Serotonina/uso terapêutico , Vimblastina/análogos & derivados , Vimblastina/uso terapêutico , Vinorelbina
7.
Mol Biotechnol ; 57(9): 801-13, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25976174

RESUMO

HERV-W is a multi-locus family of human endogenous retroviruses (HERVs) that has been found to play an important role in human physiology and pathology. Two particular members of HERV-W family are of special interests: ERVWE1 (coding syncytin-1, which is a glycoprotein essential in the formation of the placenta) and MSRV (multiple sclerosis-associated retrovirus that is thought to play a significant role in human pathology as a result of its increased expression in the brain tissue and blood cells derived from patients with multiple sclerosis (MS)). Both ERVWE1 and MSRV mRNA share high level of similarity and hence a method that allows to exclusively quantify the MSRV expression in clinical samples would be desirable. We developed a quantitative polymerase chain reaction (QPCR) technique for the detection and quantification of the multiple sclerosis-associated retrovirus. The assay utilises fluorescently labelled oligonucleotide probe, which is complementary to the conservative fragment of MSRV env gene and a peptide nucleic acid (PNA) probe, fully complementary to the ERVWE1 sequence fragment that efficiently blocks the polymerase action on ERVWE1 templates. The PNA molecule, if used parallel with hydrolysis probe in QPCR analysis, greatly facilitates the detection efficiency of MSRV even if ERVWE1 is present abundantly in respect to MSRV in the analysed sample. We achieved a wide and measurable range from 1 × 10 e(2) to 1 × 10 e(8) copies/reaction; the linearity of the technique was maintained even at the low MSRV level of 1% in respect to ERVWE1. Using our newly developed method we confirmed that the expression of MSRV takes place in normal human astrocytes and in human umbilical vein endothelial cells in vitro. We also found that the stimulation of human monocytes did not influence the specific expression of MSRV but it caused changes in mRNA level of distinct HERV-W templates.


Assuntos
Retrovirus Endógenos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Astrócitos/metabolismo , Retrovirus Endógenos/isolamento & purificação , Produtos do Gene env/genética , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Proteínas da Gravidez/genética
8.
Pharm Biol ; 53(11): 1661-70, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25856712

RESUMO

CONTEXT: Polymorphonuclear leukocytes (PMNs) produce oxidants, contributing to systemic oxidative stress. Diets rich in plant polyphenols seem to decrease the risk of oxidative stress-induced disorders including cardiovascular disease. OBJECTIVE: The objective of this study was to examine the in vitro effect of each of the 14 polyphenols on PMNs chemotaxis, intracellular calcium response, oxidants production. MATERIALS AND METHODS: Blood samples and PMNs suspensions were obtained from 60 healthy non-smoking donors and incubated with a selected polyphenol (0.5-10 µM) or a control solvent. We assessed resting and fMLP-dependent changes of intracellular calcium concentration ([Ca(2+)]i) in PMNs with the Fura-2AM method and measured fMLP-induced luminol enhanced whole blood chemiluminescence (fMLP-LBCL). Polyphenol chemoattractant activity for PMNs was tested with Boyden chambers. RESULTS: Polyphenols had no effect on resting [Ca(2+)]i. Unaffected by other compounds, fMLP-dependent increase of [Ca(2+)]i was inhibited by quercetin and catechol (5 µM) by 32 ± 14 and 12 ± 10% (p < 0.04), respectively. Seven of the 14 tested substances (5 µM) influenced fMLP-LBCL by decreasing it. Catechol, quercetin, and gallic acid acted most potently reducing fMLP-LBCL by 49 ± 5, 42 ± 15, and 28 ± 18% (p < 0.05), respectively. 3,4-Dihydroxyhydrocinnamic, 3,4-dihydroxyphenylacetic, 4-hydroxybenzoic acid, and catechin (5 µM) revealed distinct (p < 0.02) chemoattractant activity with a chemotactic index of 1.9 ± 0.8, 1.8 ± 0.7, 1.6 ± 0.6, 1.4 ± 0.2, respectively. CONCLUSION AND DISCUSSION: Catechol, quercetin, and gallic acid at concentrations commensurate in human plasma strongly suppressed the oxidative response of PMNs. Regarding quercetin and catechol, this could result from an inhibition of [Ca(2+)]i response.


Assuntos
Cálcio/metabolismo , Quimiotaxia/fisiologia , Luminescência , N-Formilmetionina Leucil-Fenilalanina/toxicidade , Neutrófilos/metabolismo , Fenóis/farmacologia , Adulto , Quimiotaxia/efeitos dos fármacos , Feminino , Humanos , Líquido Intracelular/efeitos dos fármacos , Líquido Intracelular/metabolismo , Masculino , Neutrófilos/efeitos dos fármacos , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia
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