RESUMO
The high prevalence of the combination of arterial hypertension (AH) with coronary heart disease (CHD) suggests the improvement of their treatment methods. In this regard, it is of interest to assess the dynamics of the clinical picture of patients against the background of pathogenetically determined subcellular and systemic changes under the influence of laser therapy (LT). OBJECTIVE: To evaluate the clinical effect of LT in patients with hypertension in combination with coronary artery disease and trace its relationship with the dynamics of the structure of the lipid bilayer of the erythrocyte membrane and changes in the microvascular bed. MATERIAL AND METHODS: We examined 65 male patients (mean age 50.9±6.3 years) with II-III degree AH in combination with coronary artery disease with angina pectoris. Among them, 40 patients received a 10-day course of LT, and 25 patients underwent simulated laser irradiation. At the initial stage and after 1 month, all patients underwent a bicycle exercise test, a study of the lipid composition of the erythrocyte membrane, including the main fractions of phospholipids and free cholesterol, as well as the level of intracellular Ca2+ and lipid peroxidation products - malondialdehyde and diene conjugates. Microcirculation was assessed using the method of conjunctival biomicroscopy. RESULTS: One month after the course of LT, patients showed a significant increase in exercise tolerance by 37.8%, a decrease in systolic blood pressure with a standard load by 9.9%. The improvement of the clinical picture occurred against the background of a decrease in the activity of lipid peroxidation and structural changes in the cell membrane: an increase in polyunsaturated fractions of phospholipids and a decrease in the cholesterol content, as well as a decrease in the Ca2+ level in the cell from 0.23 [0.19; 0.32] to 0.20 [0.16; 0.26] mmol/l. The results of the analysis of conjunctival biomicroscopy demonstrated a statistically significant decrease in the ratio of arteriolovenular calibers, a limitation of the severity of sludge syndrome by 59%, and an almost twofold (from 3.9±0.52 to 7.2±1.23 cap/mm2) increase in capillary density. CONCLUSION: The data obtained showed that in patients with hypertension in combination with coronary artery disease, LT causes positive changes in the lipid structure of the cell membrane and microcirculation parameters, which is accompanied by a hypotensive effect and an improvement in the clinical and functional state of patients.
Assuntos
Doença da Artéria Coronariana , Hipertensão , Terapia a Laser , Adulto , Colesterol/análise , Colesterol/metabolismo , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/metabolismo , Membrana Eritrocítica/química , Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/efeitos da radiação , Feminino , Humanos , Hipertensão/complicações , Hipertensão/radioterapia , Masculino , Microcirculação , Pessoa de Meia-Idade , Fosfolipídeos/análise , Fosfolipídeos/metabolismoRESUMO
Biomimetic approach offers numerous opportunities to design therapeutic platforms with enhanced antitumor performance and biocompatibility. Herein we report red blood cell membrane-camouflaged nanoparticles (RBC(M(TPC-PTX))) for synergistic chemo- and photodynamic therapy (PDT). Specifically, the inner core is mainly constructed by reactive oxygen species (ROS)-responsive PTX dimer (PTX2-TK) and photosensitizer 5,10,15,20-tetraphenylchlorin (TPC). In vitro experiments show that the prepared RBC(M(TPC-PTX)) is readily taken up into endosomes. Under appropriate light irradiation, the TPC can generate ROS, not only for PDT but also for triggering PTX2-TK cleavage and on-demand PTX release for chemotherapy. In vivo results show that the coating of RBC membrane prolongs blood circulation and improves tumor accumulation. The combination of chemo- and photodynamic therapy enhances anticancer therapeutic activity, and light-triggered drug release reduces systematic toxicity. All these characteristics render the described technology extremely promising for cancer treatment.
Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Preparações de Ação Retardada/metabolismo , Membrana Eritrocítica/metabolismo , Neoplasias/tratamento farmacológico , Paclitaxel/administração & dosagem , Fármacos Fotossensibilizantes/administração & dosagem , Animais , Antineoplásicos Fitogênicos/farmacocinética , Antineoplásicos Fitogênicos/farmacologia , Dimerização , Membrana Eritrocítica/efeitos da radiação , Feminino , Células HeLa , Humanos , Luz , Camundongos Nus , Nanopartículas/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Paclitaxel/farmacocinética , Paclitaxel/farmacologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacocinética , Fármacos Fotossensibilizantes/farmacologia , Pró-Fármacos , Espécies Reativas de Oxigênio/metabolismoRESUMO
PURPOSE: Storage and ionizing radiation of human red blood cells (RBC) produce alterations on RBC membranes and modify their normal shape and functionality. We investigated early morphological and biochemical changes in RBC due to those stressing agents at the nanoscale level and their impact on blood quality. MATERIALS AND METHODS: Whole blood samples from healthy donors were γ-irradiated with 15, 25, 35, and 50 Gy. Non-irradiated and non-stored RBC were used as control samples. Irradiated blood samples were stored separately at 4 °C and analyzed immediately and after 5 and 13 d. Atomic force microscopy (AFM), osmotic fragility and Raman spectroscopy were used to detect morphological and biochemical changes. RESULTS: RBC function is challenged by both irradiation and storage. The storage procedure caused nanometric variations over the surface of RBC membrane for both irradiated and non-irradiated cells. The membrane of RBC became more fragile, while the biochemical fingerprint of hemoglobin (Hb) remained unaltered. CONCLUSIONS: Our work shows that the irradiation procedure leads to an increase in the number and size of nanovesicles along with the dose. The functionality of RBC can be affected from changes in the roughness, becoming more fragile and susceptible to breakage.
Assuntos
Membrana Eritrocítica/efeitos da radiação , Raios gama/efeitos adversos , Nanotecnologia , Adulto , Humanos , Fragilidade Osmótica/efeitos da radiação , Adulto JovemRESUMO
Mesoporous silica nanoparticles (MSNs), with their large surface area and tunable pore sizes, have been widely applied for anticancer therapeutic cargos delivery with a high loading capacity. However, easy aggregation in saline buffers and limited blood circulation lifetime hinder their delivery efficiency and the anticancer efficacy. Here, new multifunctional MSNs-supported red-blood-cell (RBC)-mimetic theranostic nanoparticles with long blood circulation, deep-red light-activated tumor imaging and drug release were reported. High loading capacities were achieved by camouflaging MSNs with RBC membrane to co-load an anticancer drug doxorubicin (Dox) (39.1 wt%) and a near-infrared photosensitizer chlorin e6 (Ce6) (21.1 wt%). The RBC membrane-coating protected drugs from leakage, and greatly improved the colloidal stability of MSNs, with negligible particle size change over two weeks. Upon an external laser stimuli, the RBC membrane could be destroyed, resulting in 10 times enhancement of Dox release. In a 4T1 breast cancer mouse model, the RBC-mimetic MSNs could realize in vivo tumor imaging with elongated tumor accumulation lifetime for over 24 h, and laser-activated tumor-specific Dox accumulation. The RBC-mimetic MSNs could integrate the Ce6-based photodynamic therapy and Dox-based chemotherapy, completely suppress the primary tumor growth and inhibit metastasis of breast cancer, which could provide a new strategy for optimization of MSNs and efficient anticancer drug delivery.
Assuntos
Antineoplásicos/farmacocinética , Portadores de Fármacos/administração & dosagem , Liberação Controlada de Fármacos/efeitos da radiação , Membrana Eritrocítica/efeitos da radiação , Lasers , Nanopartículas/administração & dosagem , Dióxido de Silício/administração & dosagem , Animais , Antineoplásicos/administração & dosagem , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Clorofilídeos , Modelos Animais de Doenças , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Camundongos , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/farmacocinética , Porfirinas/administração & dosagem , Porfirinas/farmacocinéticaRESUMO
Our aim was to study the influence of low doses (0.2-4 µGy) of α radiation on the stability of human erythrocytes isolated from healthy and diabetic erythrocytes. Absorption spectroscopy was used to measure the level of red blood cell (RBC) hemolysis, along with Mössbauer spectroscopy, which is a highly specific method suited to monitoring various hemoglobin forms. States of hemoglobin are sensitive to a homeostatic imbalance in red blood cells. Changes in the membrane skeleton organization of irradiated erythrocytes isolated from healthy donors were studied using atomic force microscopy (AFM). Hemolysis, in healthy red blood cells, showed characteristic discontinuities, depending on the α particle flux and the exposure time to the low doses applied. This phenomenon was not observed in severe diabetic cases, which could be a result of modified protein-lipid-sugar complexes and the attenuation/absence of some antioxidative enzymatic processes in their RBC membranes. Similar effects were also observed for red blood cells treated with low doses of neutron and γ-radiation. AFM measurements demonstrated a reorganization of the RBC membrane skeleton network depending on the time of RBC exposure to α radiation. This suggests that the changes in the activity of the acute defense processes against free radicals which are activated within the erythrocyte membrane irradiated with α-particles could additionally be up- or down regulated by modifications to the membrane-skeleton network. However, even the highest dose of α radiation applied in these studies did not cause any significant changes in the ability of hemoglobin to transport oxygen. Microsc. Res. Tech. 80:131-143, 2017. © 2016 Wiley Periodicals, Inc.
Assuntos
Partículas alfa , Relação Dose-Resposta à Radiação , Eritrócitos/efeitos da radiação , Células Cultivadas , Membrana Eritrocítica/efeitos da radiação , Raios gama , Hemoglobinas/metabolismo , Hemólise/efeitos da radiação , Homeostase/efeitos dos fármacos , Humanos , Microscopia de Força AtômicaRESUMO
Due to widespread of human exposure to electromagnetic fields, there has been increasing public concern about the potential health risks from low-frequency electromagnetic fields; ELF-EMF. The magnetic fields (MFs) affects functions of the living organisms, such as DNA synthesis and ion transportation through the cell membranes. In the present work, the effects of short-term exposure to magnetic fields (MFs) prior to incubation were investigated on the biophysical blood properties of chicks hatched from layer-type breeder eggs. The eggs were exposed to a MF of 0.75 mT at 50 Hz for 20, 40 and 60 min before incubation. This study was performed by measuring the dielectric relaxation of hemoglobin (Hb) molecules and the membrane solubility of red blood cells (RBCs) using the non-ionic detergent octylglucoside. Exposure of the eggs to a MF increased the conductivity of the Hb molecules. The pronounced increase in the conductivity of the exposed eggs might be attributed to an increase in the surface charge of the Hb macromolecules, resulted from the formation of highly active molecular species. This speculation can be supported by the increase in the relaxation time of the exposed groups. The solubilization process of the RBC membrane indicates a loss in the mobility of RBCs in the blood of hatching chicks.
Assuntos
Sangue/efeitos da radiação , Galinhas/fisiologia , Campos Magnéticos/efeitos adversos , Óvulo/efeitos da radiação , Algoritmos , Animais , Animais Recém-Nascidos , Fenômenos Biofísicos/efeitos da radiação , Condutividade Elétrica , Membrana Eritrocítica/química , Membrana Eritrocítica/efeitos da radiação , Hemoglobinas/química , Hemoglobinas/efeitos da radiação , SolubilidadeRESUMO
The influence of nanomolar concentrations of the uranyl ion on the parameters of some membrane structures of rodent erythrocytes (laboratory mice and tundra voles--classical objects of radioecological monitoring) was investigated in vitro. A high sensitivity of the tundra vole red blood cells to the uranyl influence was shown. This fact may be determined by the cross-species difference in the membrane structures of erythrocytes--the low sphingomyelin content in tundra voles. Investigation into the phospholipid composition of the erythrocytes incubated in vitro with uranyl ions demonstrates the absence of the membrane lipid component reactions "typical" for the cells circulating in blood and also the changes pointing to the initial stages of eryptosis. Latent alterations in the membrane structure of red blood cells of both species induced by a short time contact with uranyl ions were confirmed by the increase in their sensitivity to nonionic detergent Triton X-100 and indicate the changes in orderliness of the membrane lipid phase.
Assuntos
Cloretos , Membrana Eritrocítica/efeitos da radiação , Eritrócitos/efeitos da radiação , Urânio , Animais , Arvicolinae , Membrana Eritrocítica/química , Eritrócitos/química , Lipídeos de Membrana/química , Camundongos , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Esfingomielinas/química , Esfingomielinas/metabolismoRESUMO
Object of the research was to study the diffractometric indices of erythrocytes, while 1 ml of the blood of the experimental animals was irradiated extracorporally by helium-neon laser. For this purpose 1 ml blood was taken from normal weight, (1200 gr) grown up shinshila rabbits, that we divided into 7 groups and irradiated with 10 vat helium-neon laser during 0.5-1 minutes. After irradiation blood was injected back to the organism of rabbits. After 2-6 hours from irradiation blood was taken from veins, to study by electronic microscope and later to be processed by diffractometric analysis method. The examinations testify that after extracorporeal irradiation diffractometric characteristics of erythrocytes' membranes are lower than after general irradiation, which indicates to the different energetic possibilities of laser. The extracorporeal irradiation, performed by laser and input of radiated blood back to organism is considered to be a shock therapy from the side of erythrocytes, which promote the defense function of the organism itself. The base for the shock therapy should be important factors such as homeostasis, compensative-adaptive mechanisms and so on. Exactly this above mentioned should be manifested after the sensitized cells are led back to the body (1 ml of blood) and with their existence they should promote display of the defense mechanisms.
Assuntos
Deformação Eritrocítica/efeitos da radiação , Membrana Eritrocítica/efeitos da radiação , Eritrócitos/efeitos da radiação , Animais , Eritrócitos/ultraestrutura , Lasers , CoelhosRESUMO
PURPOSE: To investigate the effects of the imposed low dose rate ionizing field on membrane stability of human erythrocytes under modulation of transmembrane exchange of Ca(2+). MATERIALS AND METHODS: Osmotic resistance of human erythrocytes was determined by a measure of haemoglobin released from erythrocytes when placed in a medium containing serial dilutions of Krebs isotonic buffer. The zeta potential as indicator of surface membrane potential was calculated from value of the cellular electrophoretic mobility. The irradiation of erythrocyte suspensions carried out by applying suitable aliquots of (90)Sr in incubation media. RESULTS: Irradiation of human erythrocytes by (90)Sr (1.5-15.0 µGy·h(-1)) induced a reversible increase of hyposmotic hemolysis and negative charge value on the outer membrane surface as well as changed responses these parameters to modification of Ca(2+) fluxes with calcimycin and nitrendipine. CONCLUSIONS: Findings indicate that the low dose rate radionuclides ((90)Sr) field modifies both Ca(2+)-mediated, and Ca(2+)-independent cellular signalling regulating mechanical stability of erythrocyte membrane. A direction of that modification presumably depends on the initial structure of membranes, and it is determined by the quality and quantitative parameters of changes in membrane structure caused by concrete operable factors.
Assuntos
Cálcio/metabolismo , Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/efeitos da radiação , Pressão Osmótica/efeitos da radiação , Transporte Biológico/efeitos da radiação , Relação Dose-Resposta à Radiação , Humanos , Radioisótopos de Estrôncio/farmacologiaRESUMO
BACKGROUND: Understanding the metabolites that are altered by donor red blood cell (RBC) storage and irradiation may provide insight into the metabolic pathways disrupted by the RBC storage lesion. STUDY DESIGN AND METHODS: Patterns of metabolites, representing more than 11,000 distinct mass-to-charge ratio (m/z) features, were compared between gamma-irradiated and nonirradiated CPDA-1-split RBCs from six human donors over 35 days of storage using multilevel sparse partial least squares discriminant analysis (msPLSDA), hierarchical clustering, pathway enrichment analysis, and network analysis. RESULTS: In msPLSDA analysis, RBC units stored 7 days or fewer (irradiated or nonirradiated) showed similar metabolomic profiles. By contrast, donor RBCs stored 10 days or more demonstrated distinct clustering as a function of storage time and irradiation. Irradiation shifted metabolic features to those seen in older units. Hierarchical clustering analysis identified at least two clusters of metabolites that differentiated between RBC units based on storage time and irradiation exposure, confirming results of the msPLSDA analysis. Pathway enrichment analysis, used to map the discriminatory biochemical features to specific metabolic pathways, identified four pathways significantly affected by irradiation and/or storage including arachidonic acid (p = 3.3 × 10(-33)) and linoleic acid (p = 1.61 × 10(-11)) metabolism. CONCLUSION: RBC storage under blood bank conditions produces numerous metabolic alterations. Gamma irradiation accentuates these differences as the age of blood increases, indicating that at the biochemical level irradiation accelerates metabolic aging of stored RBCs. Metabolites involved in the cellular membrane are prominently affected and may be useful biomarkers of the RBC storage lesion.
Assuntos
Preservação de Sangue , Eritrócitos/efeitos da radiação , Raios gama , Metaboloma/efeitos da radiação , Adenina , Citratos , Envelhecimento Eritrocítico , Membrana Eritrocítica/efeitos da radiação , Eritrócitos/metabolismo , Glucose , Humanos , Análise dos Mínimos Quadrados , Redes e Vias Metabólicas/efeitos da radiação , Pessoa de Meia-Idade , Soluções Farmacêuticas , Fosfatos , Fatores de TempoRESUMO
Antioxidant phytochemicals in fruits and vegetables of a vegetarian diet may account for the reduced risk of aging and stress oxidative associated diseases. In this study, a simple, rapid and accurate new bioassay for the determination of the antioxidant activity of purified or crude plant extracts and thier interactions is described, based on the fluorimetric determination of thiobarbituric acid reactive substances (TBARS) released by UV-B radiated red blood cell (RBC) ghosts. Pure resveratrol, white and red wine and pomegranate juice (PJ) were used as antioxidant source to test the biological method. TBARS production is a function of radiation time, the number of RBC ghosts in the radiated sample and the loaded antioxidant. The antioxidant activity of resveratrol was detected at a submicromolar concentration range [0.02 µg/mL-0.1 µmol/L]. The activity of red wine was almost 10 times higher than that of white wine, and PJ juice had the highest activity. Submaximal protective effects of PJ and red wine were additive.
Assuntos
Antioxidantes/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Membrana Eritrocítica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Bebidas , Membrana Eritrocítica/efeitos da radiação , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Eritrócitos/efeitos da radiação , Lythraceae , Masculino , Ratos Sprague-Dawley , Resveratrol , Sensibilidade e Especificidade , Estilbenos/farmacologia , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Raios Ultravioleta , VinhoRESUMO
The biostimulating activity of low level laser radiation of various wavelengths and energy doses is widely documented in the literature, but the mechanisms of the intracellular reactions involved are not precisely known. The aim of this paper is to evaluate the influence of low level laser radiation from an multiwave locked system (MLS) of two wavelengths (wavelength = 808 nm in continuous emission and 905 nm in pulsed emission) on the human erythrocyte membrane and on the secondary structure of human serum albumin (HSA). Human erythrocytes membranes and HSA were irradiated with laser light of low intensity with surface energy density ranging from 0.46 to 4.9 J cm(-2) and surface energy power density 195 mW cm(-2) (1,000 Hz) and 230 mW cm(-2) (2,000 Hz). Structural and functional changes in the erythrocyte membrane were characterized by its fluidity, while changes in the protein were monitored by its secondary structure. Dose-dependent changes in erythrocyte membrane fluidity were induced by near-infrared laser radiation. Slight changes in the secondary structure of HSA were also noted. MLS laser radiation influences the structure and function of the human erythrocyte membrane resulting in a change in fluidity.
Assuntos
Membrana Eritrocítica/efeitos da radiação , Fluidez de Membrana/efeitos da radiação , Estrutura Secundária de Proteína/efeitos da radiação , Albumina Sérica/efeitos da radiação , Relação Dose-Resposta à Radiação , Humanos , Lasers , Luz , Proteínas de Membrana/efeitos da radiação , Albumina Sérica/ultraestruturaRESUMO
An investigation into the effects of irradiation and of the storage time on aging and quality are a relevant issue to ensure the safety and the efficiency of irradiation in the prevention of transfusion-associated graft-versus-host disease (TA-GVHD). In this work, the biochemical properties and alterations presented by erythrocyte membranes, up to 28-days post-irradiation, with a dose of 25 Gy, were studied as a function of storage and post-irradiation time. There was a considerable variation in the total of phospholipid content, when comparing the control and irradiated samples, mostly from the third day onwards; and at the same time, the effect occurred as a function on the storage time of blood bags. The levels of total cholesterol decreased 3-9 days after irradiation. TBARS levels were increased after irradiation and 7 days of storage, but no increment of catalase activity was observed after the irradiation. Furthermore, the protein profile was maintained throughout the irradiation and storage time, until the 21st day, with the presence of a protein fragmentation band of around 28 kDa on the 28th day. In conclusion, although gamma irradiation is the main agent for the prevention of TA-GVHD, a better understanding of the physical and biochemical properties of erythrocytes are necessary to better assess their viability, and to be able to issue more secure recommendations on the shelf life of blood bags, and the safe use of the irradiated red cells therein.
Assuntos
Preservação de Sangue , Colesterol/química , Eritrócitos/efeitos da radiação , Raios gama , Fosfolipídeos/química , Catalase/metabolismo , Relação Dose-Resposta à Radiação , Membrana Eritrocítica/química , Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/efeitos da radiação , Eritrócitos/química , Eritrócitos/metabolismo , Peroxidação de Lipídeos/efeitos da radiação , Lipídeos de Membrana/química , Oxirredução , Proteólise , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismoRESUMO
To evaluate radiation-induced changes in the structural state of the membranes, blood samples of healthy donors were subjected to gamma radiation in the range of small (1-10 cGy) and medium doses (50 cGy-2 Gy). After irradiation, the microviscosity of lipid membranes of red and white blood cells was measured by ESR spin probe method. At doses exceeding 1 cGy, statistically significant changes of the degree of spontaneous erythrocyte hemolysis and of the lymphocyte plasma membrane microviscosity were observed. Under identical irradiation conditions, the stability of lymphocyte membranes was less as compared to erythrocyte membranes.
Assuntos
Membrana Eritrocítica/efeitos da radiação , Peroxidação de Lipídeos/efeitos da radiação , Linfócitos/efeitos da radiação , Lipídeos de Membrana/efeitos da radiação , Espectroscopia de Ressonância de Spin Eletrônica , Membrana Eritrocítica/metabolismo , Eritrócitos/efeitos da radiação , Raios gama , Humanos , Linfócitos/metabolismo , Masculino , Lipídeos de Membrana/metabolismoRESUMO
The influence of nanomolar concentrations of UO2Cl2 on the erythrocyte sensitivity (in vitro) to the factors inducing acute oxidative stress was investigated. It was shown that even a short-run exposure of uranyl ions resulted in the changes of the physico-chemical properties of the membrane. It can affectnot only the survival of cells but significantly modify their reaction on the effect of damaging factors, particularly on the impact of oxidative stress inductors. The character of modification depends on a radical source and results from the mechanisms of their effects on the cell and the ability of uranyl to catalyze ROS-forming processes. The detailed investigation into the mechanisms of the effect of uranyl ions at low concentration on cells is required.
Assuntos
Cloretos/farmacologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/efeitos da radiação , Oxidantes/farmacologia , Estresse Oxidativo , Urânio/farmacologia , Amidinas/farmacologia , Animais , Células Cultivadas , Relação Dose-Resposta à Radiação , Membrana Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/efeitos da radiação , Eritrócitos/metabolismo , Hemólise/efeitos dos fármacos , Hemólise/efeitos da radiação , Peróxido de Hidrogênio/farmacologia , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiaçãoRESUMO
The paper represents the results of research of some functional indices of blood plasma and erythrocytes in rats obtained on days 1 and 5 after exposure of the organism to low intensive electromagnetic irradiation (EMI) with 900 MHz frequency using the following two irradiation schemes: single 2 h/1 day and fractional 0.5 h/4 days. According to the data obtained, a significant increase of lipid peroxidation (LPO) intensity is registered in animal erythrocyte membranes after the influence of 900 MHz frequency EMI irrespective of the scheme applied. Inhibition of the activity of low-molecular non-enzymatic water-soluble blood antioxidants and enhancement of blood plasma LPO processes is observed on the background of a single prolonged exposure. Stimulation of the antioxidant activity with an abrupt decrease in the blood LPO activity takes place after exposure to fractional irradiation. Single long-lasting exposure, rather than intermittent shortterm exposure to 900 MHz frequency EMI facilitates the appearance of shifts in the activity of Ca(2+)-dependent K(+)-channels of erythrocytes and hyperpolarization of erythrocytes membranes.
Assuntos
Membrana Eritrocítica/efeitos da radiação , Eritrócitos/efeitos da radiação , Peroxidação de Lipídeos/efeitos da radiação , Animais , Antioxidantes/metabolismo , Radiação Eletromagnética , RatosRESUMO
Posttranslational modifications (PTMs) have been reported in hemoglobin (Hb) treated with ROS/RNS in cell-free experiments. However, little is known about oxidative PTMs of Hb occurring within the erythrocytes. The aim of this study is to characterize the patterns of Hb PTMs in erythrocytes under oxidative stress. Using mass spectrometry, we investigated specifically methionine/tryptophan oxidation, tyrosine nitration, and the modification via 4-hydroxynonenal (HNE), a product of lipid-peroxidation, on Hb. We demonstrated that the treatment with H(2)O(2)/nitrite induced higher levels of Hb oxidation/nitration in purified Hb preparations than in unpurified hemolysates and erythrocytes, indicating that ROS/RNS are primarily removed by antioxidative mechanisms. We further studied Hb from erythrocytes exposed to γ-irradiation. An irradiation of 30-100 Gy triggered a remarkable increase of intracellular ROS. However, 30 Gy did not induce apparent changes in Hb oxidation/nitration and hemolysis, while Hb oxidation/nitration and hemolysis were significantly enhanced by 100 Gy, suggesting that Hb oxidation/nitration are the consequence of overwhelmed antioxidative mechanisms after oxidative attack and reflect the severity of the oxidative damage of erythrocytes. Although irradiation was known to induce lipid-peroxidation, we could not detect HNE-Hb adducts in irradiated erythrocytes. Analyzing PTM patterns suggests Hb nitration as a more suitable indicator of the oxidative damage of erythrocytes.
Assuntos
Eritrócitos/metabolismo , Hemoglobinas/química , Nitritos/química , Processamento de Proteína Pós-Traducional , Aldeídos/química , Aldeídos/farmacologia , Sequência de Aminoácidos , Células Cultivadas , Relação Dose-Resposta à Radiação , Membrana Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/efeitos da radiação , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/efeitos da radiação , Raios gama , Hemoglobinas/metabolismo , Hemólise/efeitos dos fármacos , Hemólise/efeitos da radiação , Humanos , Peróxido de Hidrogênio/farmacologia , Metionina/química , Metionina/metabolismo , Dados de Sequência Molecular , Nitritos/metabolismo , Oxirredução , Estresse Oxidativo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Triptofano/química , Triptofano/metabolismo , Tirosina/análogos & derivados , Tirosina/química , Tirosina/metabolismoRESUMO
The comparative analysis of the blood erythrocyte lipid composition of the laboratory mice (males and females) after exposure to the chronic radiation action at the dose of 8 cGy during the early stages of the ontogeny was performed within the early and remote periods after irradiation. This action is shown to cause the marked effect both on the quantitative changes in the lipid composition and the structural state of the blood erythrocyte lipid component as follows from the numerous disturbances of the correlation interrelations between parameters of the lipid composition which are due to the structural state of the erythrocyte membrane. The most substantial changes in the blood erythrocyte lipid composition were detected for males within the remote period after the exposure, which provides evidence in favor of the disorder in the hemopoiesis process. The data obtained allow us to suggest that the erythrocyte membrane viscosity under the chronic low intensity irradiation is supported by the balance maintenance between the relative content of the phospholipid lysoforms and the molar ratio of the [sterols]/[phospholipids].
Assuntos
Desenvolvimento Embrionário , Membrana Eritrocítica/efeitos da radiação , Metabolismo dos Lipídeos/efeitos da radiação , Lipídeos de Membrana/sangue , Animais , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/efeitos da radiação , Feminino , Raios gama , Masculino , Camundongos , Fosfolipídeos/sangue , Doses de RadiaçãoRESUMO
Mid-Ultraviolet (UVB) has a significant influence on human health. In this study, human erythrocytes were exposed to UVB to investigate the effects of UVB radiation on erythrocytes membrane. And Micro-Raman spectroscopy was employed to detect the damage. Principal component analysis (PCA) was used to classify the control erythrocytes and the irradiated erythrocytes. Results showed that the erythrocytes membrane was damaged by Mid-Ultraviolet (UVB) radiation. The intensity of the Raman peaks at 1126 cm(-1) and 1082 cm(-1) were used to calculate the Longitudinal Order-Parameters in Chains (S(trans)) which can present the liquidity and ionic permeability of erythrocyte membrane. After UVB radiation for 30 min, both the liquidity and ionic permeability decreased. At the same time, the intensity of the peaks at 1302 cm(-1) (α-helix), 1254 cm(-1) (random coil), 1452 cm(-1) and 1430 cm(-1) (CH(2)/CH(3) stretch) have also changed which indicated the membrane protein also been damaged by UVB. In the whole process of radiation, the more UVB radiation dose the more damage on the erythrocyte membrane.
Assuntos
Membrana Eritrocítica/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Adulto , Células Cultivadas , Membrana Eritrocítica/patologia , Humanos , Lipídeos de Membrana/efeitos da radiação , Proteínas de Membrana/efeitos da radiação , Análise de Componente Principal , Análise Espectral RamanRESUMO
We studied the influence of low doses of γ radiation (from 0.04 to 1.8 mGy) on the stability of human red blood cells (RBC) from healthy donors and diabetic patients using absorption spectroscopy. Because of the alteration of many enzymatic pathways in diabetic RBCs resulting in strong modification of the lipid and protein membrane components one could expect that the ionizing γ-radiation should influence the stability of the healthy and diabetic cells in a different way. Indeed, distinct discontinuities and monotonic changes of hemolysis detected in the healthy and diabetic RBCs suggest that various enzymatic and chemical processes are activated in these membranes by γ radiation. Mössbauer measurements showed that only the highest applied dose of γ radiation caused modification of hemoglobin in both types of RBCs.