RESUMEN
Osteoarthritis associated with hip dysplasia is one of the most common orthopedic abnormalities in dogs, with an incidence of up to 40% in some breeds. Tissue therapy of cartilage has received great attention, with use of mesenchymal stromal cells and different types of biomaterials. The present study aimed to evaluate the effect of platelet lysate (PL) on the proliferation and differentiation of canine adipose tissue-derived mesenchymal stromal cells (ASCs), in liquid culture or hydrogels. PL was prepared from blood collected from healthy dogs and submitted to freezing-thawing cycles, and hydrogel was formed with canine thrombin. The effect of PL on the proliferation and differentiation of canine ASCs was evaluated in liquid and hydrogel systems, with microscopy, quantification of dsDNA, histology and quantification of glycosaminoglycans. The addition of 5% or 10% PL to the culture medium induced a greater proliferation rate than the presence of 10% fetal bovine serum. The cultivation of ASCs in PL gel, with normal or chondrogenic medium, resulted in maintenance of proliferation level similar to the conventional 2D cultivation, and induction of chondrogenic differentiation, especially in the presence of the chondrogenesis induction medium.
Asunto(s)
Tejido Adiposo/fisiología , Condrogénesis/fisiología , Liasas/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Animales , Plaquetas/enzimología , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Perros , Relación Dosis-Respuesta a Droga , Liasas/administración & dosificación , Células Madre Mesenquimatosas/fisiologíaRESUMEN
OBJECTIVES: Expression of phospholipids and related molecules could provide panels of multiple biomarkers searching for the signature of Alzheimer's disease (AD). The aim of the present study was to quantify ten phospholipids and simultaneously determine phospholipase A2 (PLA2) activity in blood of mild cognitive impairment (MCI) and AD patients. METHODS: Thirty-four AD, 20 MCI and 25 controls were enrolled. The phospholipids where analysed using the AbsoluteIDQ® p180 Kit. PLA2 activities were accessed in platelets by a radio-enzymatic assay. RESULTS: The study failed to fix the ten phospholipids as a panel to predict AD; the levels of PCaaC36:6, PCaaC40:6 and C16:1-OH were lower in MCI than in controls (P = 0.041, P = 0.012, P = 0.044 respectively). PCaaC40:2 levels were lower in MCI than in AD (P = 0.041). The converters MCI-AD showed at baseline lower levels of PCaaC40:2 (P = 0.050) and PCaaC40:6 (P = 0.037) than controls. iPLA2 activity was reduced in AD and MCI than in controls (P < 0.001). We found positive correlation in the control group between PCaaC38:6 and tPLA2 (r = 0.680; P = 0.001) and sPLA2 (r = 0.601; P = 0.004); PCaaC40:1 and iPLA2 (r = 0.503; P = 0.020); PCaaC40:6 and tPLA2 (r = 0.532; P = 0.013) and sPLA2 (r = 0.523; P = 0.015). CONCLUSIONS: Lipids metabolites in plasma might indirectly indicate changes in neuronal membrane and this deregulation can outline the transition between healthy and diseased brains.
Asunto(s)
Enfermedad de Alzheimer/enzimología , Disfunción Cognitiva/enzimología , Fosfolipasas A2/sangre , Fosfolípidos/sangre , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/sangre , Biomarcadores/sangre , Plaquetas/enzimología , Estudios de Casos y Controles , Disfunción Cognitiva/sangre , Femenino , Humanos , Metabolismo de los Lípidos , Masculino , Pruebas NeuropsicológicasRESUMEN
The purinergic system has an important role in the regulation of vascular functions. The interference of thyroid hormones in this system and in cardiovascular events has been studied in recent years. However, the mechanisms involved in vascular, purinergic, and oxidative changes in thyroid disorders are not completely understood. Therefore, the present study aimed to assess purinergic enzyme activity in platelets from rats with hypothyroidism and hyperthyroidism induced, respectively, by continuous exposure to methimazole (MMI) at 20 mg/100 mL or L-thyroxine at 1.2 mg/100 mL in drinking water for 1 month. Results showed that rats exposed to L-thyroxine had a significant decrease in NTPDase activity, wherein ATP hydrolysis was 53% lower and ADP hydrolysis was 40% lower. Moreover, ecto-5'-nucleotidase activity was decreased in both groups, by 39% in the hypothyroidism group and by 52% in the hyperthyroidism group. On the other hand, adenosine deaminase (ADA) activity was increased in hyperthyroidism (75%), and nucleotide pyrophosphatase/phosphodiesterase (NPP) activity was increased in animals with hypothyroidism (127%) and those with hyperthyroidism (128%). Our findings suggest that changes in purinergic enzyme and purine levels could contribute to the undesirable effects of thyroid disturbances. Moreover, oxidative stress and, in particular, a high level of ROS production, showed a causal relation with changes in ectonucleotidase activity and nucleotide and nucleoside levels.
Asunto(s)
5'-Nucleotidasa/metabolismo , Adenosina Desaminasa/metabolismo , Antígenos CD/metabolismo , Apirasa/metabolismo , Plaquetas/enzimología , Hipertiroidismo/enzimología , Hipotiroidismo/enzimología , Nucleótidos/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Hidrólisis , Hipertiroidismo/sangre , Hipertiroidismo/inducido químicamente , Hipotiroidismo/sangre , Hipotiroidismo/inducido químicamente , Masculino , Metimazol/toxicidad , Estrés Oxidativo , Ratas , Ratas WistarRESUMEN
Signaling mediated by purines is a widespread mechanism of cell-cell communication related to vasomotor responses and the control of platelet function in the vascular system. However, little is known about the involvement of this signaling as well as the role of reactive oxygen species (ROS) in the development of hypothyroidism. Therefore, the present study investigates changes in the purinergic system, including enzyme activities and expression in platelets, and oxidative profiles in patients with post-thyroidectomy hypothyroidism. The nucleoside triphosphate diphosphohydrolase 1 (NTPDase/CD39) expression in patients increased by 40%, and the adenosine triphosphate (ATP) or adenosine diphosphate (ADP) hydrolyzing activity increased by 82% and 70%, respectively. The activities of ecto-5´-nucleotidase and adenosine deaminase (ADA) also significantly enhanced (39% and 52%, respectively), which correlates with a 45% decrease in adenosine concentration. Furthermore, these patients demonstrated an increased production of ROS (42%), thiobarbituric acid reactive substances (TBARS) (115%), carbonyl protein (30%) and a decreased glutathione S-transferase (GST) activity (20%). This study demonstrates that hypothyroidism interferes with adenine nucleoside and nucleotide hydrolysis and this is correlated with oxidative stress, which might be responsible for the increase in ADA activity. This increase causes rapid adenosine deamination, which can generate a decrease in their concentration in the systemic circulation, which can be associated with the development of vascular complications.
Asunto(s)
Apirasa/sangre , Plaquetas/enzimología , Regulación Enzimológica de la Expresión Génica , Hipotiroidismo/sangre , Especies Reactivas de Oxígeno/sangre , Tiroidectomía , Adenosina Difosfato/sangre , Adenosina Trifosfato/sangre , Adulto , Anciano , Plaquetas/patología , Femenino , Humanos , Hipotiroidismo/etiología , Hipotiroidismo/patología , Masculino , Persona de Mediana EdadRESUMEN
Sepsis is a potentially lethal condition, and it is associated with platelet alterations. The present study sought to investigate the activity of ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase), E-5'-nucleotidase, and ecto-adenosine deaminase (E-ADA) in the platelets of rats that were induced with sepsis. Male Wistar rats were divided into three groups of ten animals each: a negative control group (normal; NC); a group that underwent surgical procedures (sham); and a group that underwent cecal ligation and perforation (CLP). The induction of sepsis was confirmed by bacteremia, and the causative pathogen identified was Escherichia coli. Hematological parameters showed leukocytosis and thrombocytopenia in animals in the septic group. The results also revealed that there were significant (p < 0.05) increases in adenosine triphosphate (ATP) and adenosine monophosphate (AMP) hydrolyses, and in the deamination of adenosine in the CLP group compared to the sham and control groups. Conversely, ADP hydrolysis was significantly decreased (p < 0.05) in the CLP group compared to the sham and control groups. Purine levels were analyzed by high-performance liquid chromatography (HPLC) in serum samples from control, sham, and CLP groups. Increased concentrations of ATP, adenosine, and inosine were found in the CLP group compared to the sham and control groups. Conversely, the concentrations of ADP and AMP in the CPL group were not significantly altered. We suggest that alterations in hematological parameters, nucleotide hydrolysis in platelets, and nucleotide concentrations in serum samples of rats with induced sepsis may be related to thromboembolic events.
Asunto(s)
5'-Nucleotidasa/metabolismo , Plaquetas/enzimología , Ciego/cirugía , Ligadura/efectos adversos , Complicaciones Posoperatorias/enzimología , Sepsis/enzimología , Adenosina Monofosfato/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Plaquetas/metabolismo , Humanos , Masculino , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/metabolismo , Complicaciones Posoperatorias/microbiología , Ratas , Ratas Wistar , Sepsis/etiología , Sepsis/metabolismo , Sepsis/microbiologíaRESUMEN
The enzymatic activities of NTPDase, 5'-nucleotidase and adenosine deaminase (ADA) are important in regulating the concentration of adenine nucleotides, molecules known to be involved on platelet aggregation. Fasciolosis causes coagulation disorders that have not been completely elucidated. Taking into consideration the association between the purinergic system and hemostasis, this study aimed to evaluate the enzymatic activities of NTPDase (hydrolyze ATP and ADP), 5'-nucleotidase (hydrolyze AMP) and ADA (deamination of adenosine) in platelets from cattle experimentally infected by Fasciola hepatica on days 20, 40, 60 and 80 post-infection (PI). For this study, 10 healthy Friesian steers were separated into two groups: the group A (n = 5) was used as uninfected control, and the group B was composed of steers experimentally infected by F. hepatica (n = 5). The number of platelets did not differ between groups in the periods evaluated. Reduction of NTPDase (p < 0.05) hydrolysing ATP (days 20, 40 and 60 PI), and ADP (days 40, 60 and 80 PI), and on 5'-nucleotidase hydrolyzing AMP (days 40 and 60 PI) was observed. A reduction (p < 0.05) in ADA activity on day 20 PI, as well as an increase (p < 0.05) in ADA activity on days 40 and 60 PI was observed when compared to the control. Based on these results, we can conclude that ATP, ADP and AMP hydrolysis and adenosine deamination were altered in platelets of cattle infected by F. hepatica. Considering the importance of the purinergic system in hemostasis, it is believed that those changes may contribute to the coagulation impairment observed in acute fasciolosis described in the literature.
Asunto(s)
Adenosina Desaminasa/sangre , Plaquetas/enzimología , Enfermedades de los Bovinos/parasitología , Fascioliasis/veterinaria , Nucleotidasas/sangre , Animales , Bovinos , Enfermedades de los Bovinos/sangre , Enfermedades de los Bovinos/enzimología , Fasciola hepatica/fisiología , Fascioliasis/sangre , Fascioliasis/enzimología , Heces/parasitología , Hígado/parasitología , Hígado/patología , Masculino , Recuento de Huevos de Parásitos/veterinaria , Recuento de Plaquetas/veterinariaRESUMEN
Methylglyoxal (MG) is a reactive dicarbonyl metabolite originated mainly from glucose degradation pathway that plays an important role in the pathogenesis of diabetes mellitus (DM). Reactions of MG with biological macromolecules (proteins, DNA and lipids) can induce cytotoxicity and apoptosis. Here, human erythrocytes, leukocytes and platelets were acutely exposed to MG at concentration ranging from 0.025 to 10 mM. Afterwards, hemolysis and osmotic fragility in erythrocytes, DNA damage and cell viability in leukocytes, and the activity of purinergic ecto-nucleotidases in platelets were evaluated. The levels of glycated products from leukocytes and free amino groups from erythrocytes and platelets were also measured. MG caused fragility of membrane, hemolysis and depletion of amino groups in erythrocytes. DNA damage, loss of cell viability and increased levels of glycated products were observed in leukocytes. In platelets, MG inhibited the activity of enzymes NTPDase, 5'-nucleotidase and adenosine deaminase (ADA) without affecting the levels of free amino groups. Our findings provide insights for understanding the mechanisms involved in MG acute toxicity towards distinct blood cells.
Asunto(s)
Plaquetas/efectos de los fármacos , Daño del ADN , Eritrocitos/efectos de los fármacos , Leucocitos/efectos de los fármacos , Piruvaldehído/toxicidad , 5'-Nucleotidasa/metabolismo , Adenosina Desaminasa/metabolismo , Adulto , Plaquetas/enzimología , Plaquetas/patología , Supervivencia Celular/efectos de los fármacos , Ensayo Cometa , Relación Dosis-Respuesta a Droga , Eritrocitos/enzimología , Eritrocitos/patología , Femenino , Hemólisis/efectos de los fármacos , Humanos , Leucocitos/enzimología , Leucocitos/patología , Masculino , Fragilidad Osmótica/efectos de los fármacosRESUMEN
The human immunodeficiency virus (HIV) infection results in biochemical and vascular dysfunctions. The highly active antiretroviral therapy (HAART) markedly reduces mortality and opportunistic diseases associated with acquired immunodeficiency syndrome (AIDS). This increased survival time predisposes the development of cardiovascular diseases. Platelets present purinergic system ectoenzymes such as E-NTPDase, E-5'-nucleotidase and E-ADA on its surface. In view of this, the aim of this study was to evaluate the activity of these ectoenzymes in platelets as well as the platelet aggregation and lipid profile of patients with HIV infection and also patients receiving HAART. The results showed an increase in the E-NTPDase activity for ATP hydrolysis in the HIV group compared with the control group and the HIV/HAART group. When assessing the activity E-NTPDase hydrolysis to ADP, the results revealed an increase in activity in the HIV group when compared to the control group, and a decrease in activity when in the HIV/HAART group when compared to the control and HIV groups. The activity of E-5'-nucleotidase revealed an increase in AMP hydrolysis in the HIV group, as the results from control and HIV/HAART groups showed no statistical difference. Regarding the E-ADA activity, the HIV and HIV/HAART groups revealed a decreased deamination of adenosine when compared with the control group. Furthermore, we observed an increased platelet aggregation of HIV/HAART group compared with the control group. Thus, our results suggest that antiretroviral treatment against HIV has a significant effect on the activity of purinergic system ectoenzymes demonstrating that thromboregulation is involved in the process.
Asunto(s)
Nucleótidos de Adenina/metabolismo , Terapia Antirretroviral Altamente Activa , Plaquetas/metabolismo , Infecciones por VIH/sangre , Infecciones por VIH/tratamiento farmacológico , Trombosis/tratamiento farmacológico , 5'-Nucleotidasa/metabolismo , Adenosina Desaminasa/metabolismo , Adulto , Antígenos CD/metabolismo , Coagulación Sanguínea , Plaquetas/enzimología , Estudios de Casos y Controles , Citometría de Flujo , Humanos , Hidrólisis , Lípidos/sangre , Agregación Plaquetaria , Trombosis/complicacionesRESUMEN
Metabolic Syndrome (MetS) has become a worldwide epidemic, alongside with a high socioeconomic cost, and its diagnostic criteria must include at least three out of the five features: visceral obesity, hypertension, dyslipidemia, insulin resistance, and high fasting glucose levels. MetS shows an increased oxidative stress associated with platelet hyperactivation, an essential component for thrombus formation and ischemic events in MetS patients. Platelet aggregation is governed by the peroxide tone and the activity of Protein Disulfide Isomerase (PDI) at the cell membrane. PDI redox active sites present active cysteine residues that can be susceptible to changes in plasma oxidative state, as observed in MetS. However, there is a lack of knowledge about the relationship between PDI and platelet hyperactivation under MetS and its metabolic features, in spite of PDI being a mediator of important pathways implicated in MetS-induced platelet hyperactivation, such as insulin resistance and nitric oxide dysfunction. Thus, the aim of this review is to analyze data available in the literature as an attempt to support a possible role for PDI in MetS-induced platelet hyperactivation.
Asunto(s)
Plaquetas/enzimología , Plaquetas/patología , Síndrome Metabólico/complicaciones , Síndrome Metabólico/enzimología , Proteína Disulfuro Isomerasas/metabolismo , Animales , Humanos , Modelos Biológicos , Estrés OxidativoRESUMEN
Reduced phospholipase A2 (PLA2) activity and increased phosphorylation of glycogen synthase kinase 3B (GSK3B) participate in the production of beta-amyloid plaques and of neurofibrillary tangles, which are two neuropathological hallmarks of Alzheimer's disease (AD). Experimental evidences suggest a neuroprotective effect of the cholinesterase inhibitor donepezil in the treatment the disease. The aims of the present study were to evaluate in AD patients the effects of treatment with donepezil on PLA2 activity and GSK3B level. Thirty patients with AD were treated during 6 months with 10 mg daily of donepezil. Radio-enzymatic assays were used to measure PLA2 activity and Elisa assays for GSK3B level, both in platelets. Before treatment and after 3 and 6 months on donepezil, AD patients underwent a cognitive assessment and platelet samples were collected. Values were compared to a healthy control group of 42 sex- and age-matched elderly individuals. Before treatment, iPLA2 activity was lower in patients with AD as compared to controls (p < 0.001). At baseline, no differences were found in GSK3B level between both groups. After 3 and 6 months of treatment, we found a significant increase in iPLA2 activity (p = 0.015 and p < 0.001, respectively). iPLA2 increment was related to the cognitive improvement during treatment (p = 0.037). After 6 months, we found an increase in phosphorylated GSK3B (p = 0.02). The present findings suggest two possible mechanisms by which donepezil delays the progression of AD. The increment of iPLA2 activity may reduce the production of beta-amyloid plaques, whereas the phosphorylation of GSK3B inactivates the enzyme, reducing thus the phosphorylation of tau protein.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Plaquetas/enzimología , Inhibidores de la Colinesterasa/uso terapéutico , Glucógeno Sintasa Quinasa 3/metabolismo , Fosfolipasas A2 Grupo VI/metabolismo , Indanos/uso terapéutico , Piperidinas/uso terapéutico , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/sangre , Análisis de Varianza , Donepezilo , Femenino , Humanos , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Fosforilación , Factores de TiempoRESUMEN
BACKGROUND: In addition to their key role in hemostasis, platelets and megakaryocytes regulate immune and inflammatory responses, in part through their expression of Toll-like receptors (TLRs). Among the TLRs, TLR3 recognizes dsRNA associated with viral infection. Thrombocytopenia is a frequent complication of viral infection. However, the expression and functionality of TLR3 in megakaryocytes and platelets is not yet well understood. OBJECTIVE: To study the expression and functionality of TLR3 in the megakaryocytic lineage. METHODS AND RESULTS: RT-PCR, flow cytometric and immunofluorescence assays showed that TLR3 is expressed in CD34(+) cells, megakaryocytes, and platelets. Immunoblotting assays showed that stimulation of megakaryocytes with two synthetic agonists of TLR3, Poly(I:C) and Poly(A:U), activated the nuclear factor-κB (NF-κB), phosphoinositide 3-kinase (PI3K)/Akt, extracellular signal-related kinase (ERK)1/2 and p38 pathways. TLR3-megakaryocyte activation resulted in reduced platelet production in vitro and interferon-ß release through the PI3K-Akt and NF-κB signaling pathways. TLR3 ligands potentiated the aggregation mediated by classic platelet agonists. This effect was also observed for ATP release, but not for P-selectin or CD40L membrane exposure, indicating that TLR3 activation was not involved in α-granule release. In addition, TLR3 agonists induced activation of the NF-κB, PI3K-Akt and ERK1/2 pathways in platelets. Reductions in platelet production and platelet fibrinogen binding mediated by Poly(I:C) or Poly(A:U) were prevented by the presence of an inhibitor of the TLR3-dsRNA complex. CONCLUSIONS: Our findings indicate that functional TLR3 is expressed in CD34(+) cells, megakaryocytes, and platelets, and suggest a potential role for this receptor in the megakaryopoiesis/thrombopoiesis alterations that occur in viral infections.
Asunto(s)
Linaje de la Célula , Megacariocitos/metabolismo , Receptor Toll-Like 3/metabolismo , Plaquetas/enzimología , Plaquetas/metabolismo , Células Madre Hematopoyéticas/metabolismo , Humanos , Megacariocitos/citología , Transducción de SeñalRESUMEN
Glycogen synthase kinase-3B (GSK-3B) is involved with important neuronal processes such as cell survival, gene regulation, mood and cognitive performance. This enzyme is inactivated by phosphorylation at the phospho-Ser9 site. We compared GSK-3B levels in patients with schizophrenia to a health control group. The levels of phosphorylated and total GSK-3B in platelets of ten drug-free patients, ten long-term olanzapine treated patients and 20 healthy controls were determined by means of an enzyme immunoassay kit. In drug-free patients, GSK-3B levels were accessed again after 8 weeks on treatment with olanzapine. At baseline, drug-free patients presented lower phosphorylated and total GSK-3B levels than healthy controls (p < 0.05). After 8 weeks on olanzapine treatment, phosphorylated and total GSK-3B levels were significantly increased (p < 0.01). Reduced phospho-Ser9-GSK-3B in schizophrenia may disrupt signal-transduction pathways and influence crucial cellular processes, such as transcription, apoptosis, stress response and cell proliferation. Further studies should clarify whether the increment of GSK-3B phosphorylation by olanzapine is related to its antipsychotic effects.
Asunto(s)
Antipsicóticos/uso terapéutico , Benzodiazepinas/uso terapéutico , Plaquetas/enzimología , Glucógeno Sintasa Quinasa 3/metabolismo , Esquizofrenia/sangre , Esquizofrenia/tratamiento farmacológico , Adulto , Plaquetas/efectos de los fármacos , Femenino , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Olanzapina , Fosforilación/efectos de los fármacos , Escalas de Valoración Psiquiátrica , Estadísticas no Paramétricas , Factores de TiempoRESUMEN
OBJECTIVE: Phospholipases A2 (PLA2 ) comprise a family of hydrolytic enzymes that cleave membrane phospholipids and play a key role in cellular homeostasis. Alterations in enzymatic activity have been hypothesized in bipolar disorder (BD). Recent studies suggest that PLA2 activity in platelets may reflect PLA2 activity in the brain. The aim of this study was to determine PLA2 activity in platelets of BD patients. METHODS: We determined the activity of PLA2 subtypes [extracellular, calcium-dependent PLA2 (sPLA2 ), intracellular, calcium-dependent PLA2 (cPLA2 ), and intracellular, calcium-independent PLA2 (iPLA2 )] by a radioenzymatic method in platelets from 20 patients with BD (15 drug-naïve and five drug-free) and from 16 age- and gender-matched healthy controls. RESULTS: We found that iPLA2 , cPLA2 , and sPLA2 activities were lower in drug-naïve patients with BD when compared to the control group (p = 0.017, p < 0.001, and p < 0.001, respectively). CONCLUSIONS: Reduced PLA2 activity at the early stage of BD may disrupt brain function and increase the risk for the disease. Moreover, epidemiological studies show that patients with BD have a fivefold increased risk for developing Alzheimer's disease. Because patients with Alzheimer's disease also have reduced PLA2 activity, the present finding of reduced PLA2 in the BD group may be related to the risk factor for these individuals developing Alzheimer's disease in advanced age.
Asunto(s)
Trastorno Bipolar , Plaquetas/enzimología , Encéfalo/enzimología , Fosfolipasas A2/metabolismo , Adulto , Trastorno Bipolar/sangre , Trastorno Bipolar/diagnóstico , Calcio/metabolismo , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Masculino , Fosfolípidos/metabolismo , Escalas de Valoración Psiquiátrica , Factores de RiesgoRESUMEN
BACKGROUND: Heart failure (HF) patients are at an increased risk of thrombotic events. Here, we investigated the effects of exercise training on platelet function and factors involved in its modulation in HF. DESIGN AND METHODS: Thirty HF patients were randomized to 6 months of supervised exercise training or to a control group that remained sedentary. Exercise training consisted of 30 min of moderate-intensity treadmill exercise, followed by resistance and stretching exercises, performed three times a week. Blood was collected before and after the intervention for platelet and plasma obtainment. RESULTS: Peak VO2 increased after exercise training (18.0 ± 2.2 vs. 23.8 ± 0.5 mlO2/kg/min; p < 0.05). Exercise training reduced platelet aggregation induced by both collagen and ADP (approximately -6%; p < 0.05), as well as platelet nitric oxide synthase activity (0.318 ± 0.030 vs. 0.250 ± 0.016 pmol/10(8) cells; p < 0.05). No difference in the above-mentioned variables were observed in the control group. No significant difference was observed in intraplatelet cyclic guanosine monophosphate levels among groups. There was a significant increase in the activity of the antioxidant enzymes superoxide dismutase and catalase in plasma and platelets, resulting in a decrease in both lipid and protein oxidative damage. Systemic levels of the inflammatory markers C-reactive protein, fibrinogen, and tumour necrosis factor α were also reduced in HF after training. CONCLUSIONS: Our results suggest that regular exercise training is a valuable adjunct to optimal medical management of HF, reducing platelet aggregation via antioxidant and anti-inflammatory effects, and, therefore, reducing the risk of future thrombotic events.
Asunto(s)
Antioxidantes/metabolismo , Terapia por Ejercicio/métodos , Insuficiencia Cardíaca/terapia , Mediadores de Inflamación/sangre , Inflamación/prevención & control , Estrés Oxidativo , Agregación Plaquetaria , Trombosis/prevención & control , Biomarcadores/sangre , Plaquetas/enzimología , Plaquetas/inmunología , Brasil , GMP Cíclico/sangre , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/inmunología , Humanos , Inflamación/sangre , Inflamación/inmunología , Lípidos/sangre , Masculino , Persona de Mediana Edad , Actividad Motora , Ejercicios de Estiramiento Muscular , Óxido Nítrico Sintasa/sangre , Consumo de Oxígeno , Pruebas de Función Plaquetaria , Valor Predictivo de las Pruebas , Estudios Prospectivos , Recuperación de la Función , Entrenamiento de Fuerza , Factores de Riesgo , Trombosis/sangre , Trombosis/diagnóstico , Factores de Tiempo , Resultado del TratamientoRESUMEN
OBJECTIVE: It has been postulated that mood stabilizers inhibit glycogen synthase kinase 3-beta (Gsk3ß) activity, mainly through its phosphorylation on serine-9 (Ser9). However, in vivo studies addressing Gsk3ß activity in patients with bipolar disorder are scarce. Here, we compare Gsk3ß inactivation (as indicated by Ser9-phosphorylation) in platelets of elderly patients with bipolar disorder undergoing clinical treatment and healthy elderly adults not taking medication. METHODS: Platelet samples were obtained from 37 elderly adults (bipolar disorder = 19, controls = 18). Relative changes in Gsk3ß inactivation was estimated by comparing the ratios of phosphorylated Gsk3ß to total Gsk3ß (p-Gsk3ß Ser9/Gsk3ß) between the disease and control groups. RESULTS: Phosphorylated-Gsk3ß (p < 0.001) and the p-Gsk3ß Ser9/Gsk3ß ratio (p = 0.006) were elevated in bipolar patients. In the bipolar disorder group, p-Gsk3ß Ser9/Gsk3ß was positively correlated with serum lithium levels (r = 0.478, p = 0.039). CONCLUSIONS: Gsk3ß inactivation is higher in this group of elderly adults undergoing treatment for bipolar disorder. However, whether the treatment or the disease causes Gsk3ß inactivation was confounded by the lack of an unmedicated, bipolar control group and the non-uniform treatment regimens of the bipolar disorder group. Thus, further studies should help distinguish whether Gsk3ß inactivation is an effect of drug treatment or an intrinsic characteristic of bipolar disorder.
Asunto(s)
Trastorno Bipolar/enzimología , Plaquetas/enzimología , Glucógeno Sintasa Quinasa 3/sangre , Anciano , Anciano de 80 o más Años , Trastorno Bipolar/tratamiento farmacológico , Estudios de Casos y Controles , Femenino , Glucógeno Sintasa Quinasa 3 beta , Humanos , Masculino , Persona de Mediana Edad , Fosforilación , Psicotrópicos/uso terapéuticoRESUMEN
The phospholipase A2 (PLA2) enzymes have been implicated in several neuropsychiatry disorders and activity alterations have been described in brain and platelet. Since brain tissue is not readily available for the measurement of PLA2 activity, it would be of interest to test directly whether PLA2 activities in both tissues are correlated. We performed this task assessing PLA2 activity in platelets and hippocampus collected simultaneously from 19 patients undergoing temporal lobectomy for treatment of refractory epilepsy. Our findings suggest that total PLA2 activity in platelets may reflect the total activity of the enzyme in the brain (rs=0.59, p=0.008). However in our sample no correlations were found between the subgroups of the enzyme in brain and in platelets. This lack of correlations may be due to different effects of drug treatment on the PLA2 subtypes. In face of the difficulty to obtain brain tissues from living patients, further studies with larger drug-free samples are warranted to clarify whether the use of platelets is a reliable strategy to reflect the subtypes of PLA2 activity in the brain.
Asunto(s)
Plaquetas/enzimología , Epilepsia del Lóbulo Temporal/enzimología , Hipocampo/enzimología , Fosfolipasas A2/metabolismo , Adulto , Lobectomía Temporal Anterior , Epilepsia del Lóbulo Temporal/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
This study evaluated the effects of caffeic acid on ectonucleotidase activities such as NTPDase (nucleoside triphosphate diphosphohydrolase), Ecto-NPP (nucleotide pyrophosphatase/phosphodiesterase), 5'-nucleotidase and adenosine deaminase (ADA) in platelets and lymphocytes of rats, as well as in the profile of platelet aggregation. Animals were divided into five groups: I (control); II (oil); III (caffeic acid 10 mg/kg); IV (caffeic acid 50 mg/kg); and V (caffeic acid 100 mg/kg). Animals were treated with caffeic acid diluted in oil for 30 days. In platelets, caffeic acid decreased the ATP hydrolysis and increased ADP hydrolysis in groups III, IV and V when compared to control (P<0.05). The 5'-nucleotidase activity was decreased, while E-NPP and ADA activities were increased in platelets of rats of groups III, IV and V (P<0.05). Caffeic acid reduced significantly the platelet aggregation in the animals of groups III, IV and V in relation to group I (P<0.05). In lymphocytes, the NTPDase and ADA activities were increased in all groups treated with caffeic acid when compared to control (P<0.05). These findings demonstrated that the enzymes were altered in tissues by caffeic acid and this compound decreased the platelet aggregation suggesting that caffeic acid should be considered a potentially therapeutic agent in disorders related to the purinergic system.
Asunto(s)
Nucleótidos de Adenina/metabolismo , Plaquetas/efectos de los fármacos , Ácidos Cafeicos/farmacología , Linfocitos/efectos de los fármacos , Adenosina Desaminasa/metabolismo , Adenosina Trifosfatasas/metabolismo , Animales , Plaquetas/enzimología , Relación Dosis-Respuesta a Droga , Hidrólisis , Linfocitos/enzimología , Masculino , Hidrolasas Diéster Fosfóricas/metabolismo , Agregación Plaquetaria/efectos de los fármacos , Pirofosfatasas/metabolismo , Ratas , Ratas WistarRESUMEN
This study investigated the ex vivo effects of the moderate red wine (RW) and grape juice (GJ) consumption, and the in vitro effects of the resveratrol, caffeic acid, gallic acid, quercetin, and rutin on NTPDase (nucleoside triphosphate diphosphohydrolase), ecto-nucleotide pyrophosphatase/phosphodiesterase (E-NPP), 5'-nucleotidase, and adenosine deaminase (ADA) activities in platelets and platelet aggregation from streptozotocin-induced diabetic rats. The animals were divided into six groups (n = 10): control/saline, control/GJ, control/RW, diabetic/saline, diabetic/GJ, and diabetic/RW. RW and GJ were administered for 45 days; after this period, the blood was collected for experimental determinations. Results showed that NTPDase, E-NPP, 5'-nucleotidase, and ADA activities as well as platelet aggregation were increased in the diabetic/saline group compared to the control/saline group. Treatment with RW and GJ increased ectonucleotidases activities and prevented the increase in the ADA activity in the diabetic/GJ and diabetic/RW groups. Platelet aggregation was also decreased by the treatment with RW and GJ in the diabetic/GJ and diabetic/RW groups. In the in vitro tests, resveratrol, caffeic acid, and gallic acid increased ATP, ADP, and AMP hydrolysis, while quercetin and rutin decreased the hydrolysis of these nucleotides in platelets of diabetic rats. The ADA activity and platelet aggregation were reduced in platelets of diabetic rats in the presence of all polyphenols tested in vitro. These findings suggest that RW, GJ, and all polyphenols tested were able to modulate the ectoenzymes activities. Moreover, a decrease in the platelet aggregation was observed and it could contribute to the prevention of platelet abnormality, and consequently vascular complications in diabetic state.
Asunto(s)
Nucleótidos de Adenina/metabolismo , Diabetes Mellitus Experimental/metabolismo , Preparaciones de Plantas/farmacología , Agregación Plaquetaria/efectos de los fármacos , Vitis/química , Vino , 5'-Nucleotidasa/metabolismo , Adenosina Desaminasa/metabolismo , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Bebidas , Plaquetas/efectos de los fármacos , Plaquetas/enzimología , Plaquetas/metabolismo , Ácidos Cafeicos/farmacología , Diabetes Mellitus Experimental/sangre , Relación Dosis-Respuesta a Droga , Hidrólisis/efectos de los fármacos , Masculino , Pirofosfatasas/metabolismo , Quercetina/farmacología , Ratas , Ratas Wistar , Resveratrol , Rutina/farmacología , Estilbenos/farmacologíaRESUMEN
Reactive oxygen species have emerged as important molecules in cardiovascular function. Recent research has shown that the NADPH oxidases are important sources of superoxide in vascular cells and myocytes. The NADPH oxidases vascular share some, but not all, of the characteristics of the enzyme in neutrophils, both produce superoxide, which is metabolized to hydrogen peroxide, at the same time these reactive oxygen species serve as second messengers activate multiple intracellular signalling pathways. NADPH oxidases are essential in the physiological response of vascular cellsto pathological states such as atherosclerosis, and are functionally relevant in activation and recruitment of platelets. Recent studies suggest a key role for NADPH oxidase in the formation of a specific product from the oxidation of arachidonic acid, and a potential role in the process of recruitment of platelets. Taking into account these characteristics and evidence of the involvement of the NADPH oxidases in cardiovascular diseases as the thrombosis, inhibition of this enzymatic system appears as a promising therapy to treat and prevent these diseases.
Asunto(s)
Humanos , Aterosclerosis/enzimología , Especies Reactivas de Oxígeno , NADPH Oxidasas/metabolismo , Plaquetas/enzimología , Activación Plaquetaria/fisiología , Antioxidantes , Isoprostanos , PolifenolesRESUMEN
BACKGROUND AND AIMS: Nitric oxide-independent soluble guanylyl cyclase (sGC) activators reactivate the haem-oxidized enzyme in vascular diseases. This study was undertaken to investigate the anti-platelet mechanisms of the haem-independent sGC activator BAY 60-2770 in human washed platelets. The hypothesis that sGC oxidation potentiates the anti-platelet activities of BAY 60-2770 has been tested. METHODS: Human washed platelet aggregation and adhesion assays, as well as flow cytometry for α(IIb)ß(3) integrin activation and Western blot for α1 and ß1 sGC subunits were performed. Intracellular calcium levels were monitored in platelets loaded with a fluorogenic calcium-binding dye (FluoForte). RESULTS: BAY 60-2770 (0.001-10 µM) produced significant inhibition of collagen (2 µg/ml)- and thrombin (0.1 U/ml)-induced platelet aggregation that was markedly potentiated by the sGC inhibitor ODQ (10 µM). In fibrinogen-coated plates, BAY 60-2770 significantly inhibited platelet adhesion, an effect potentiated by ODQ. BAY 60-2770 increased the cGMP levels and reduced the intracellular Ca(2+) levels, both of which were potentiated by ODQ. The cell-permeable cGMP analogue 8-Br-cGMP (100 µM) inhibited platelet aggregation and Ca(2+) levels in an ODQ-insensitive manner. The cAMP levels remained unchanged by BAY 60-2770. Collagen- and thrombin-induced α(IIb)ß(3) activation was markedly inhibited by BAY 60-2770 that was further inhibited by ODQ. The effects of sodium nitroprusside (3 µM) were all prevented by ODQ. Incubation with ODQ (10 µM) significantly reduced the protein levels of α1 and ß1 sGC subunits, which were prevented by BAY 60-2770. CONCLUSION: The inhibitory effects of BAY 60-2770 on aggregation, adhesion, intracellular Ca(2+) levels and α(IIb)ß(3) activation are all potentiated in haem-oxidizing conditions. BAY 60-2770 prevents ODQ-induced decrease in sGC protein levels. BAY 60-2770 could be of therapeutic interest in cardiovascular diseases associated with thrombotic complications.