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1.
Pharmaceuticals (Basel) ; 14(3)2021 Mar 05.
Article in English | MEDLINE | ID: mdl-33807975

ABSTRACT

Cannabidiol (CBD), a lipophilic cannabinoid compound without psychoactive effects, has emerged as adjuvant of anti-epileptic drugs (AEDs) in the treatment of refractory epilepsy (RE), decreasing the severity and/or frequency of seizures. CBD is considered a multitarget drug that could act throughout the canonical endocannabinoid receptors (CB1-CB2) or multiple non-canonical pathways. Despite the fact that the CBD mechanism in RE is still unknown, experiments carried out in our laboratory showed that CBD has an inhibitory role on P-glycoprotein excretory function, highly related to RE. Since CB2 is expressed mainly in the immune cells, we hypothesized that CBD treatment could alter the activity of polymorphonuclear neutrophils (PMNs) in a similar way that it does with microglia/macrophages and others circulating leukocytes. In vitro, CBD induced PMN cytoplasmatic vacuolization and proapoptotic nuclear condensation, associated with a significantly decreased viability in a concentration-dependent manner, while low CBD concentration decreased PMN viability in a time-dependent manner. At a functional level, CBD reduced the chemotaxis and oxygen consumption of PMNs related with superoxide anion production, while the singlet oxygen level was increased suggesting oxidative stress damage. These results are in line with the well-known CBD anti-inflammatory effect and support a potential immunosuppressor role on PMNs that could promote an eventual defenseless state during chronic treatment with CBD in RE.

2.
J Alzheimers Dis ; 82(s1): S109-S126, 2021.
Article in English | MEDLINE | ID: mdl-33325385

ABSTRACT

The cerebral hypoxia-ischemia can induce a wide spectrum of biologic responses that include depolarization, excitotoxicity, oxidative stress, inflammation, and apoptosis, and result in neurodegeneration. Several adaptive and survival endogenous mechanisms can also be activated giving an opportunity for the affected cells to remain alive, waiting for helper signals that avoid apoptosis. These signals appear to help cells, depending on intensity, chronicity, and proximity to the central hypoxic area of the affected tissue. These mechanisms are present not only in a large list of brain pathologies affecting commonly older individuals, but also in other pathologies such as refractory epilepsies, encephalopathies, or brain trauma, where neurodegenerative features such as cognitive and/or motor deficits sequelae can be developed. The hypoxia inducible factor 1α (HIF-1α) is a master transcription factor driving a wide spectrum cellular response. HIF-1α may induce erythropoietin (EPO) receptor overexpression, which provides the therapeutic opportunity to administer pharmacological doses of EPO to rescue and/or repair affected brain tissue. Intranasal administration of EPO combined with other antioxidant and anti-inflammatory compounds could become an effective therapeutic alternative, to avoid and/or slow down neurodegenerative deterioration without producing adverse peripheral effects.


Subject(s)
Brain/metabolism , Hypoxia/metabolism , Inflammation Mediators/metabolism , Neurodegenerative Diseases/metabolism , Oxidative Stress/physiology , Animals , Apoptosis/drug effects , Apoptosis/physiology , Brain/drug effects , Brain/pathology , Erythropoietin/administration & dosage , Erythropoietin/metabolism , Humans , Hypoxia/drug therapy , Hypoxia/pathology , Inflammation Mediators/antagonists & inhibitors , Neurodegenerative Diseases/drug therapy , Neurodegenerative Diseases/pathology , Oxidative Stress/drug effects
3.
Nutrients ; 12(10)2020 Oct 15.
Article in English | MEDLINE | ID: mdl-33076345

ABSTRACT

Metabolic Syndrome (MetS) is increasing worldwide regardless of culture, genetic, gender, and geographic differences. While multiple individual risk factors, such as obesity, hypertension, diabetes, and hyperlipidemia, can cause cardiovascular disease (CVD), it is the intercurrence of these risk factors that defines MetS as a cluster that creates an environment for atherosclerosis and other manifestations of CVD. Despite the advances in the knowledge and management of each of the components of MetS, there are two molecular biology processes, chronic inflammation and oxidative stress, which are still underdiagnosed and undertreated. In order to assess the effect of a dietary supplement on chronic inflammation in MetS, we conducted a clinical trial with volunteers receiving a formula composed of resveratrol, piperine and alpha tocopherol (FRAMINTROL®), together with their habitual treatment, for three months. The inflammatory state was evaluated by ultrasensitive C reactive protein (US CRP) and ferritin in plasma, and oxygen consumption and chemiluminescence in neutrophils. The results showed that ferritin decreased by 10% (p < 0.05), US-CRP by 33% (p < 0.0001), oxygen consumption by 55% (p < 0.0001), and spontaneous chemiluminiscence was by 25% (p < 0.005) after treatment. As far as we know, this is the first study showing a chronic inflammation decrease in MetS patients due to the administration of a biopower Resveratrol-piperine and alpha tocopherol dietary supplement together with conventional therapy.


Subject(s)
Alkaloids/administration & dosage , Benzodioxoles/administration & dosage , Dietary Supplements , Inflammation/therapy , Metabolic Syndrome/complications , Piperidines/administration & dosage , Polyunsaturated Alkamides/administration & dosage , Resveratrol/administration & dosage , alpha-Tocopherol/administration & dosage , Aged , Alkaloids/pharmacology , Benzodioxoles/pharmacology , Biomarkers/analysis , Biomarkers/blood , C-Reactive Protein/analysis , Chronic Disease , Female , Ferritins/blood , Humans , Inflammation/diagnosis , Inflammation/etiology , Luminescent Measurements , Male , Middle Aged , Neutrophils , Oxidative Stress/drug effects , Oxygen Consumption , Piperidines/pharmacology , Polyunsaturated Alkamides/pharmacology , Resveratrol/pharmacology , Time Factors , alpha-Tocopherol/pharmacology
4.
Front Behav Neurosci ; 14: 32, 2020.
Article in English | MEDLINE | ID: mdl-32256321

ABSTRACT

Despite the constant development of new antiepileptic drugs (AEDs), more than 30% of patients develop refractory epilepsy (RE) characterized by a multidrug-resistant (MDR) phenotype. The "transporters hypothesis" indicates that the mechanism of this MDR phenotype is the overexpression of ABC transporters such as P-glycoprotein (P-gp) in the neurovascular unit cells, limiting access of the AEDs to the brain. Recent clinical trials and basic studies have shown encouraging results for the use of cannabinoids in RE, although its mechanisms of action are still not fully understood. Here, we have employed astrocytes and vascular endothelial cell cultures subjected to hypoxia, to test the effect of cannabidiol (CBD) on the P-gp-dependent Rhodamine-123 (Rho-123) efflux. Results show that during hypoxia, intracellular Rho-123 accumulation after CBD treatment is similar to that induced by the P-gp inhibitor Tariquidar (Tq). Noteworthy, this inhibition is like that registered in non-hypoxia conditions. Additionally, docking studies predicted that CBD could behave as a P-gp substrate by the interaction with several residues in the α-helix of the P-gp transmembrane domain. Overall, these findings suggest a direct effect of CBD on the Rho-123 P-gp-dependent efflux activity, which might explain why the CBD add-on treatment regimen in RE patients results in a significant reduction in seizure frequency.

5.
Curr Pharm Des ; 26(12): 1356-1364, 2020.
Article in English | MEDLINE | ID: mdl-32072891

ABSTRACT

The most important activity of erythropoietin (EPO) is the regulation of erythrocyte production by activation of the erythropoietin receptor (EPO-R), which triggers the activation of anti-apoptotic and proliferative responses of erythroid progenitor cells. Additionally, to erythropoietic EPO activity, an antiapoptotic effect has been described in a wide spectrum of tissues. EPO low levels are found in the central nervous system (CNS), while EPO-R is expressed in most CNS cell types. In spite of EPO-R high levels expressed during the hypoxicischemic brain, insufficient production of endogenous cerebral EPO could be the cause of determined circuit alterations that lead to the loss of specific neuronal populations. In the heart, high EPO-R expression in cardiac progenitor cells appears to contribute to myocardial regeneration under EPO stimulation. Several lines of evidence have linked EPO to an antiapoptotic role in CNS and in heart tissue. In this review, an antiapoptotic role of EPO/EPO-R system in both brain and heart under hypoxic conditions, such as epilepsy and sudden death (SUDEP) has been resumed. Additionally, their protective effects could be a new field of research and a novel therapeutic strategy for the early treatment of these conditions and avoid SUDEP.


Subject(s)
Drug Resistant Epilepsy , Erythropoietin , Brain/metabolism , Cardiovascular System/pathology , Erythropoietin/metabolism , Humans , Receptors, Erythropoietin/metabolism , Sudden Unexpected Death in Epilepsy
6.
Front Neurosci ; 13: 750, 2019.
Article in English | MEDLINE | ID: mdl-31379495

ABSTRACT

Erythropoietin (EPO) is not only a hormone that promotes erythropoiesis but also has a neuroprotective effect on neurons attributed to its known anti-apoptotic action. Previously, our group has demonstrated that recombinant-human EPO (rHu-EPO) can protect neurons and recovery motor activity in a chemical focal brain hypoxia model (Merelli et al., 2011). We and others also have reported that repetitive seizures can mimic a hypoxic- like condition by HIF-1α nuclear translocation and high neuronal expression P-gp. Here, we report that a single 20-min status epilepticus (SE) induces P-gp and EPO-R expression in cortical pyramidal neurons and only P-gp expression in astrocytes. In vitro, excitotoxic stress (300 µM glutamate, 5 min), can also induce the expression of EPO-R and P-gp simultaneously with both HIF-1α and NFkB nuclear translocation in primary cortical neurons. Primary astrocytes exposed to chemical hypoxia with CoCl2 (0.3 mM, 6 h) increased P-gp expression as well as an increased efflux of Rhodamine 123 (Rho123) that is a P-gp substrate. Tariquidar, a specific 3er generation P-gp-blocker was used as an efflux inhibitor control. Astrocytes treated with rHu-EPO showed a significant recovery of the Rho123 retention in a similar way as seen by Tariquidar, demonstrating for first time that rHu-EPO can inhibit the P-gp-dependent efflux activity. Taking together, these data suggest that stimulation of EPO depending signaling system could not only play a central role in brain cell protection, but this system could be a new tool for reverse the pharmacoresistant phenotype in refractory epilepsy as well as in other pharmacoresistant hypoxic brain diseases expressing P-gp.

7.
Pharmaceuticals (Basel) ; 11(1)2018 Feb 16.
Article in English | MEDLINE | ID: mdl-29462915

ABSTRACT

Sudden unexpected death in epilepsy (SUDEP) is the major cause of death in those patients suffering from refractory epilepsy (RE), with a 24-fold higher risk relative to the normal population. SUDEP risk increases with seizure frequency and/or seizure-duration as in RE and Status Epilepticus (SE). P-glycoprotein (P-gp), the product of the multidrug resistant ABCB1-MDR-1 gene, is a detoxifying pump that extrudes drugs out of the cells and can confer pharmacoresistance to the expressing cells. Neurons and cardiomyocytes normally do not express P-gp, however, it is overexpressed in the brain of patients or in experimental models of RE and SE. P-gp was also detected after brain or cardiac hypoxia. We have previously demonstrated that repetitive pentylenetetrazole (PTZ)-induced seizures increase P-gp expression in the brain, which is associated with membrane depolarization in the hippocampus, and in the heart, which is associated with fatal SE. SE can produce hypoxic-ischemic altered cardiac rhythm (HIACR) and severe arrhythmias, and both are related with SUDEP. Here, we investigate whether SE induces the expression of hypoxia-inducible transcription factor (HIF)-1α and P-gp in cardiomyocytes, which is associated with altered heart rhythm, and if these changes are related with the spontaneous death rate. SE was induced in Wistar rats once a week for 3 weeks, by lithium-pilocarpine-paradigm. Electrocardiograms, HIF-1α, and P-gp expression in cardiomyocytes, were evaluated in basal conditions and 72 h after SE. All spontaneous deaths occurred 48 h after each SE was registered. We observed that repeated SE induced HIF-1α and P-gp expression in cardiomyocytes, electrocardiographic (ECG) changes, and a high rate of spontaneous death. Our results suggest that the highly accumulated burden of convulsive stress results in a hypoxic heart insult, where P-gp expression may play a depolarizing role in cardiomyocyte membranes and in the development of the ECG changes, such as QT interval prolongation, that could be related with SUDEP. We postulate that this mechanism could explain, in part, the higher SUDEP risk in patients with RE or SE.

8.
Curr Neuropharmacol ; 16(10): 1484-1498, 2018.
Article in English | MEDLINE | ID: mdl-29318974

ABSTRACT

Neurodegeneration (NDG) is linked with the progressive loss of neural function with intellectual and/or motor impairment. Several diseases affecting older individuals, including Alzheimer's disease, Amyotrophic Lateral Sclerosis, Huntington's disease, Parkinson's disease, stroke, Multiple Sclerosis and many others, are the most relevant disorders associated with NDG. Since other pathologies such as refractory epilepsy, brain infections, or hereditary diseases such as "neurodegeneration with brain iron accumulation", also lead to chronic brain inflammation with loss of neural cells, NDG can be said to affect all ages. Owing to an energy and/or oxygen supply imbalance, different signaling mechanisms including MAPK/PI3K-Akt signaling pathways, glutamatergic synapse formation, and/or translocation of phosphatidylserine, might activate some central executing mechanism common to all these pathologies and also related to oxidative stress. Hypoxia inducible factor 1-α (HIF-1α) plays a twofold role through gene activation, in the sense that this factor has to "choose" whether to protect or to kill the affected cells. Most of the afore-mentioned processes follow a protracted course and are accompanied by progressive iron accumulation in the brain. We hypothesize that the neuroprotective effects of iron chelators are acting against the generation of free radicals derived from iron, and also induce sufficient -but not excessive- activation of HIF-1α, so that only the hypoxia-rescue genes will be activated. In this regard, the expression of the erythropoietin receptor in hypoxic/inflammatory neurons could be the cellular "sign" to act upon by the nasal administration of pharmacological doses of Neuro-EPO, inducing not only neuroprotection, but eventually, neurorepair as well.


Subject(s)
Drug Discovery , Hypoxia-Inducible Factor 1, alpha Subunit/physiology , Iron Chelating Agents/pharmacology , Neurodegenerative Diseases/drug therapy , Neurodegenerative Diseases/physiopathology , Animals , Brain/metabolism , Cell Hypoxia/physiology , Erythropoietin/pharmacology , Erythropoietin/therapeutic use , Humans , Iron/metabolism , Iron Chelating Agents/therapeutic use
9.
Curr Pharm Des ; 19(38): 6791-801, 2013.
Article in English | MEDLINE | ID: mdl-23530506

ABSTRACT

Neuronal damage secondary to brain injuries such as cerebral hypoxia, seizures as well as neurodegenerative process, may include pro-inflammatory changes. The activation of a common mechanism related to survival or cell death, mediated by the stabilization and trans-activation of Hypoxia-Inducible Factor 1 (HIF-1), has been observed in these conditions. HIF-1 may induce over expression of P-glycoprotein, the product multidrug-resistance gene (MDR-1), both on blood-brain barrier as well as on the cerebral damaged cells, producing the refractoriness to therapeutic strategies for neuroprotection. However, in these same cells, HIF-1 can also induce the expression of erythropoietin receptor (Epo-R). Irrespective of its known properties on hematopoiesis, it was proposed that erythropoietin can trigger neuroprotective mechanisms mediated by Epo-R activation. Brain hypoxia, epilepsy, neurodegeneration and inflammation, can share the induction of Epo-R and several other growth factor receptors as well as signal transductions pathways after HIF-1 transactivation. Perhaps, the use of the intranasal route for the exogenous administration of Epo, (or other biological compounds) could help neuroprotection as well as to repair the brain areas damaged.


Subject(s)
Epilepsy/drug therapy , Erythropoietin/therapeutic use , Hypoxia, Brain/drug therapy , Neurodegenerative Diseases/drug therapy , Neuroprotective Agents/therapeutic use , Animals , Epilepsy/physiopathology , Glutamic Acid/physiology , Humans , Hypoxia, Brain/physiopathology , Hypoxia-Inducible Factor 1/physiology , Neurodegenerative Diseases/physiopathology , Receptors, Erythropoietin/physiology
10.
Drug Metabol Drug Interact ; 26(2): 65-9, 2011.
Article in English | MEDLINE | ID: mdl-21756166

ABSTRACT

Stroke is a major human health problem without efficient available therapeutics. Ischemic brain injury can induce cell death as well as upregulation of endogenous adaptive mechanisms depending on the severity and duration of hypoxia, and the activity of transcription factors, such as hypoxia inducible factor 1-α (HIF-1α). HIF-1α induces gene expression as multidrug resistance (MDR-1) gene associated with drug-refractory phenotype, as well as erythropoietin (Epo) and erythropoietin receptor (Epo-R) associated with O(2) supply. The spontaneous stimulation of the Epo/Epo-R system is not enough for brain protection. Therefore, administration of exogenous recombinant human Epo (rHu-Epo) was suggested as an alternative therapy in stroke. In several experimental models of brain hypoxia, Epo and Epo variants, including rHu-Epo, showed neuroprotective effects. Intranasal administration of these Epo-compounds can reach the central nervous system and protect the brain against ischemia, avoiding hematopoietic effects. However, it has been reported that high expression of Epo-R in neurons must be available to be activated by Epo. According to these considerations, intranasal delivery of rHu-Epo could be an interesting approach in the treatment of cerebral hypoxias avoiding both (i) adverse peripheral effects of treatment with Epo in stroke, and (ii) the pharmacoresistant phenotype depending on MDR-1 expression.


Subject(s)
Erythropoietin/administration & dosage , Hypoxia, Brain/drug therapy , Neuroprotective Agents/administration & dosage , Administration, Intranasal , Animals , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/physiology , Receptors, Erythropoietin/analysis , Recombinant Proteins/administration & dosage
11.
Neurotox Res ; 20(2): 182-92, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21116766

ABSTRACT

Stroke is a major human health problem inducing long-term disability without any efficient therapeutic option being currently available. Under hypoxia, hypoxia-inducible factor-1α (HIF-1α) activates several genes as erythropoietin receptor (Epo-R) related with O(2) supply, and the multidrug-resistance gene (MDR-1) related with drug-refractory phenotype. Brain cortical injection of CoCl(2) produces focal hypoxia-like lesion with neuronal and glial alterations, as well as HIF-1α stabilization and MDR-1 overexpression. Intranasal (IN) drug delivery can by-pass blood-brain barrier (BBB) where MDR-1 is normally expressed. We evaluated the effects of IN-rHu-Epo administration on spontaneous motor activity (SMA) and the brain pattern expression of HIF-1α, MDR-1, and Epo-R in our cobalt-induced hypoxia model. Adult male Wistar rats were injected by stereotaxic surgery in frontoparietal cortex, with CoCl(2) (2 µl-50 mM; n = 20) or saline (controls; n = 20). Ten rats of each group were treated with IN-rHu-Epo 24 U or IN-saline. In addition, erythropoietic stimulation was evaluated by reticulocytes (Ret) account during three consecutive days, after intraperitoneal (i.p.)-recombinant-human Epo (rHu-Epo) (950 U; n = 6) or IN-rHu-Epo (24 U; n = 6) administration. SMA was evaluated by open field and rotarod tests, before and after surgical procedures during five consecutive days. Histological and immunostaining studies of HIF-1α, MDR-1, and Epo-R were performed on brain slides. A significant difference in SMA was observed in the hypoxic rats of IN-rHu-Epo-administered group as compared with Co-Saline-treated subjects and controls (p < 0.001). HIF-1α, EPO-R, and MDR-1 were overexpressed in the hypoxic cortex areas, while in contralateral hemisphere or controls, they were negatives. Reticulocytes were only increased in intraperitoneal (i.p.)-rHu-Epo-administered group. In spite of MDR-1 overexpression being detected in neurons, the coexpression of Epo-R could explain the positive effects observed on SMA of IN-rHu-Epo-administered group.


Subject(s)
Cobalt/toxicity , Erythropoietin/administration & dosage , Exploratory Behavior/drug effects , Hypoxia, Brain/chemically induced , Hypoxia, Brain/drug therapy , Recovery of Function/drug effects , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Administration, Intranasal , Analysis of Variance , Animals , Disease Models, Animal , Gene Expression Regulation/drug effects , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Male , Motor Activity/drug effects , Rats , Rats, Wistar , Receptors, Erythropoietin/metabolism , Recombinant Proteins , Reticulocytes/drug effects , Rotarod Performance Test
12.
Neurotox Res ; 15(4): 348-58, 2009 May.
Article in English | MEDLINE | ID: mdl-19384568

ABSTRACT

Ischemic brain injury is a dynamic process that involves oxidative stress, inflammation, and cell death, as well as activation of endogenous adaptive and regenerative mechanisms depending on activation of transcription factors such as hypoxia inducible factor 1-alpha (HIF-1alpha). Because CoCl2 activates HIF-1alpha, we described a new focal-hypoxia model by direct intracerebral CoCl2 injection. Adult male Wistar rats were intracerebrally injected with CoCl2 (2 microl-50 mM), in frontoparietal cortex of right hemisphere, and saline (2 microl) in the contralateral hemisphere. In slides of fixed brains at 1, 6, 9, 24 h or 5 day after treatment, TTC, histochemistry (toluidine blue, Hoescht-33342, TUNEL), immunostaining (HIF-1alpha, GFAP), Lycopersicon esculentum lectin staining, and electron microscopy (EM) were performed. Immediately after 1 h post CoCl2 injection, HIF-1alpha stabilization and neuronal nuclear shrinkage and cromathin condensation were observed by immunostaining and EM, respectively. Neuronal apoptotic nuclear morphology and GFAP immunoreactivity and lectin maximal reactivity were detected during 6-9 h. Ultrastructural alterations of morphology included edematous perinuclear cytoplasm, organelles and endoplasmic reticulum (RE) enlargement, mitochondrial swelling with increased matrix density, and deposits of electron-dense material. Neurons showed particular nuclear indentations. Astrocytes and oligodendrocytes presented alterations in both nuclei and RE with dilated lumen and altered mitochondrias, and all these ultrastructural changes became detectable at day 5. CoCl2 cortical injection mimics focal brain ischemia, inducing neuronal death and glial activation. This model brings the opportunity to develop focal ischemia in selected brain areas to study their functional consequences and potential pharmacological therapies for in vivo models of stroke.


Subject(s)
Antimutagenic Agents/toxicity , Cobalt/toxicity , Hypoxia/chemically induced , Hypoxia/pathology , Neuroglia/drug effects , Neurons/drug effects , Analysis of Variance , Animals , Brain/drug effects , Brain/pathology , Cell Death/drug effects , Disease Models, Animal , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , In Situ Nick-End Labeling/methods , Lectins/drug effects , Male , Microscopy, Electron, Transmission/methods , Nerve Tissue Proteins/metabolism , Neuroglia/ultrastructure , Neurons/ultrastructure , Rats , Rats, Wistar , Staining and Labeling/methods , Time Factors
13.
J Neurol Sci ; 258(1-2): 84-92, 2007 Jul 15.
Article in English | MEDLINE | ID: mdl-17459414

ABSTRACT

Neuronal damage after stroke-associated brain hypoxia is a leading cause of long-term disability and death. The refractoriness to therapeutic strategies for neuroprotection after 3 h post brain ischemia is poorly understood. P-glycoprotein (P-gp), the multidrug resistance gene (MDR-1) product is normally expressed at blood-brain-barrier. P-gp neuronal expression has been demonstrated in refractory epilepsy and after brain ischemia. In this report we investigated the hypoxia-induced neuronal P-gp expression after local injection of CoCl(2) (1-200 mM) in the fronto-parietal cortex of male adult rats (Bregma -1.30 mm) by stereotaxic surgery. P-gp immunostaining of brain slides was analyzed using specific monoclonal antibodies and double immunolabeling was done with specific astrocytic and neuronal markers. Five days after injection of 1 mM CoCl(2), P-gp expression surrounding the lesion site was observed in neurons, astrocytic end-foot on capillary blood vessels and endothelial cells on blood vessels. Higher CoCl(2) doses (200 mM) resulted in additional P-gp immunostaining of the entire astrocytic and neuronal cytoplasm. Electron microscopy (EM) studies showed alterations in neurons as early as 6 h after the CoCl(2) injection. P-gp expression in hypoxic neurons and astrocytic end-foot could potentially impair of drugs access to the brain parenchyma thus suggesting the presence of two P-gp-based pumping systems (one in astrocytes and other in the hypoxic neurons) that are able to behave as a previously unnoticed obstacle for pharmacological strategies of neuroprotection.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Gene Expression/physiology , Hypoxia/metabolism , Hypoxia/physiopathology , Neurons/metabolism , ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics , Animals , Antimutagenic Agents/administration & dosage , Cobalt/administration & dosage , Disease Models, Animal , Gene Expression/drug effects , Glial Fibrillary Acidic Protein/metabolism , Hypoxia/chemically induced , Hypoxia/pathology , Male , Microscopy, Electron, Transmission/methods , Neurons/drug effects , Neurons/ultrastructure , Parietal Lobe/drug effects , Parietal Lobe/metabolism , Parietal Lobe/pathology , Phosphopyruvate Hydratase/metabolism , Rats , Rats, Wistar
14.
Medicina [B.Aires] ; 61(5,pt.1): 552-6, 2001. tab, gra
Article in Spanish | BINACIS | ID: bin-9265

ABSTRACT

La regulación del receptor de transferrina (RTF) está relacionada con los depósitos de hierro (Fe) intracelular y guarda una relación constante con el receptor soluble presente en plasma. Se ha demostrado que en las anemias por deficiencia de Fe (AF) cuando se produce la disminución de los depósitos de Fe, aumenta la expresión del receptor. En las anemias de los procesos crónicos (APC) establecer el verdadero estado del Fe es complejo, debido a la influencia que tienen los procesos inflamatorios ó infecciosos en el equilibrio del Fe orgánico. Se estudiaron 30 sujetos sanos normales (grupo control) y 42 pacientes anémicos ( hemoglobina menor de 120 g/L) que presentaban APC con y sin deficiencia de hierro, a fin de establecer el valor diagnóstico del receptor soluble de transferrina (RTFs). Se correlacionó la eritropoyetina (EPO) como factor estimulador de la eritropoyesis , con los descensos de hemoglobina que se producen en ambos grupos. Los resultados fueron analizados aplicando el test estadístico ANOVA, no encontrándose diferencia significativa en los valores de RTFs entre los grupos de APC con y sin deficiencia de Fe. La relación log EPO versus hemoglobina (Hb) en ambos grupos mostró una correlación inversa estadísticamente significativa. Se concluye que de acuerdo a los resultados obtenidos, los valores de RTFs en estos pacientes se encuentran dentro de los rangos normales y no se relacionan con el estado del hierro orgánico. Por consiguiente, su empleo como parámetro diferencial para establecer deficiencia de hierro en las APC, no tendría aplicación diagnóstica. (AU)


Subject(s)
RESEARCH SUPPORT, NON-U.S. GOVT , Humans , Male , Female , Adult , Middle Aged , Aged , Receptors, Transferrin/blood , Erythropoietin/blood , Anemia, Iron-Deficiency/diagnosis , Receptors, Transferrin/metabolism , Erythropoietin/metabolism , Anemia, Iron-Deficiency/blood , Anemia, Iron-Deficiency/metabolism , Anemia/diagnosis , Anemia/blood , Ferritins/blood , Enzyme-Linked Immunosorbent Assay , Analysis of Variance , Biomarkers/blood
15.
Medicina (B.Aires) ; Medicina (B.Aires);61(5,pt.1): 552-6, 2001. tab, graf
Article in Spanish | LILACS | ID: lil-299678

ABSTRACT

La regulación del receptor de transferrina (RTF) está relacionada con los depósitos de hierro (Fe) intracelular y guarda una relación constante con el receptor soluble presente en plasma. Se ha demostrado que en las anemias por deficiencia de Fe (AF) cuando se produce la disminución de los depósitos de Fe, aumenta la expresión del receptor. En las anemias de los procesos crónicos (APC) establecer el verdadero estado del Fe es complejo, debido a la influencia que tienen los procesos inflamatorios ó infecciosos en el equilibrio del Fe orgánico. Se estudiaron 30 sujetos sanos normales (grupo control) y 42 pacientes anémicos ( hemoglobina menor de 120 g/L) que presentaban APC con y sin deficiencia de hierro, a fin de establecer el valor diagnóstico del receptor soluble de transferrina (RTFs). Se correlacionó la eritropoyetina (EPO) como factor estimulador de la eritropoyesis , con los descensos de hemoglobina que se producen en ambos grupos. Los resultados fueron analizados aplicando el test estadístico ANOVA, no encontrándose diferencia significativa en los valores de RTFs entre los grupos de APC con y sin deficiencia de Fe. La relación log EPO versus hemoglobina (Hb) en ambos grupos mostró una correlación inversa estadísticamente significativa. Se concluye que de acuerdo a los resultados obtenidos, los valores de RTFs en estos pacientes se encuentran dentro de los rangos normales y no se relacionan con el estado del hierro orgánico. Por consiguiente, su empleo como parámetro diferencial para establecer deficiencia de hierro en las APC, no tendría aplicación diagnóstica.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Anemia, Iron-Deficiency , Erythropoietin , Receptors, Transferrin , Analysis of Variance , Anemia , Anemia, Iron-Deficiency , Biomarkers , Enzyme-Linked Immunosorbent Assay , Erythropoietin , Ferritins , Receptors, Transferrin
16.
Medicina (B.Aires) ; Medicina (B.Aires);59(1): 11-6, 1999. tab, ilus
Article in Spanish | LILACS | ID: lil-231903

ABSTRACT

Se estudiaron 22 pacientes con neoplasias hematológicas que incluían: 12 pacientes con diagnóstico de Leucemia Mieloide Aguda (LMA) de novo, según criterio morfológico y citoquímico establecido por la FAB Comité Francés, Americano, Británico), una LMA secundaria a Síndrome mielodisplásico (SMD), y una leucemia aguda bifenotípica, donde se correlacionó la reacción citoquímica de peroxidasas con la metodología de anti-mieloperoxidasa (MPO) por fosfatasa alcalina anti-fosfatasa (AFAAF). Los estudios fueron completados con la reacción citoquímica de esterasas inespecíficas y el fenotipo inmunológico se estableció por citometría de flujo para definir la estirpe celular mieloide o linfoide. La misma técnica fue utilizada para el análisis celular de restricción de cadenas livianas kappa y lambda en 8 pacientes con desórdenes linfoproliferativos malignos de origen B que comprendían 3 casos de Leucemia a células vellosas (HCL), 1 caso de Linfoma leucemizado y 4 casos de neoplasias de células plasmáticas vs una plasmocitosis reactiva. Se concluye que las reacciones inmunocitoquímicas aplicadas a las patologías estudiadas y otras enfermedades hematopoyéticas son útiles cuando la morfología y la citoquímica no han sido conduyentes para establecer un correcto diagnóstico y para distinguir un linaje celular, por ej. linfoma tipo B y T. Sin embargo, se debe enfatizar que su uso diagnóstico es útil como técnica complementaria de los estudios histopatológicos, morfológicos, citoquímicos y fenotípicos celulares, siendo aún discutida su importancia pronóstica.


Subject(s)
Humans , Alkaline Phosphatase/analysis , Antibodies, Monoclonal/analysis , Hematologic Neoplasms/diagnosis , Immunoenzyme Techniques , Peroxidase/analysis , Flow Cytometry , Hematologic Neoplasms/enzymology
17.
Medicina [B.Aires] ; 59(1): 11-6, 1999. tab, ilus
Article in Spanish | BINACIS | ID: bin-16366

ABSTRACT

Se estudiaron 22 pacientes con neoplasias hematológicas que incluían: 12 pacientes con diagnóstico de Leucemia Mieloide Aguda (LMA) de novo, según criterio morfológico y citoquímico establecido por la FAB Comité Francés, Americano, Británico), una LMA secundaria a Síndrome mielodisplásico (SMD), y una leucemia aguda bifenotípica, donde se correlacionó la reacción citoquímica de peroxidasas con la metodología de anti-mieloperoxidasa (MPO) por fosfatasa alcalina anti-fosfatasa (AFAAF). Los estudios fueron completados con la reacción citoquímica de esterasas inespecíficas y el fenotipo inmunológico se estableció por citometría de flujo para definir la estirpe celular mieloide o linfoide. La misma técnica fue utilizada para el análisis celular de restricción de cadenas livianas kappa y lambda en 8 pacientes con desórdenes linfoproliferativos malignos de origen B que comprendían 3 casos de Leucemia a células vellosas (HCL), 1 caso de Linfoma leucemizado y 4 casos de neoplasias de células plasmáticas vs una plasmocitosis reactiva. Se concluye que las reacciones inmunocitoquímicas aplicadas a las patologías estudiadas y otras enfermedades hematopoyéticas son útiles cuando la morfología y la citoquímica no han sido conduyentes para establecer un correcto diagnóstico y para distinguir un linaje celular, por ej. linfoma tipo B y T. Sin embargo, se debe enfatizar que su uso diagnóstico es útil como técnica complementaria de los estudios histopatológicos, morfológicos, citoquímicos y fenotípicos celulares, siendo aún discutida su importancia pronóstica. (AU)


Subject(s)
Humans , Hematologic Neoplasms/diagnosis , Immunoenzyme Techniques , Antibodies, Monoclonal/analysis , Peroxidase/analysis , Alkaline Phosphatase/analysis , Flow Cytometry , Hematologic Neoplasms/enzymology
18.
Medicina (B.Aires) ; Medicina (B.Aires);43(6,pt.1): 653-8, 1983.
Article in Spanish | LILACS | ID: lil-18104

ABSTRACT

Se estudio la funcion bactericida de los neutrofilos en 20 pacientes con sepsis grave, 9 con infecciones moderadas y 17 voluntarios sanos.La actividad bactericida se midio mediante la prueba de reduccion del azul de nitrotetrazolio (NBT), utilizando uma tecnica estimulada por Staphylococcus epidermidis y cuantificable colorimetricamente. Los resultados revelaron que ambos grupos de pacientes diferian significativamente del grupo control (p < 0.01) Los datos expuestos demostraron una inhibicion de la respuesta neutrofila en la sepsis severa, que contrasta con los valores altos de reduccion del NBT hallados en los procesos infecciosos de menor gravedad Esta disminuicion en la capacidad bactericida de los neutrofilos hallada en pacientes septicos a pesar de la estimulacion y descartada una disfuncion hereditaria del sistema fagocitario puede considerarse un defecto adquirido producido posiblemente por el mismo proceso septico


Subject(s)
Adolescent , Adult , Middle Aged , Humans , Male , Female , Bacterial Infections , Neutrophils , Nitroblue Tetrazolium , Sepsis
19.
Medicina [B.Aires] ; 43(6,pt.1): 653-8, 1983.
Article in Spanish | BINACIS | ID: bin-34429

ABSTRACT

Se estudio la funcion bactericida de los neutrofilos en 20 pacientes con sepsis grave, 9 con infecciones moderadas y 17 voluntarios sanos.La actividad bactericida se midio mediante la prueba de reduccion del azul de nitrotetrazolio (NBT), utilizando uma tecnica estimulada por Staphylococcus epidermidis y cuantificable colorimetricamente. Los resultados revelaron que ambos grupos de pacientes diferian significativamente del grupo control (p < 0.01) Los datos expuestos demostraron una inhibicion de la respuesta neutrofila en la sepsis severa, que contrasta con los valores altos de reduccion del NBT hallados en los procesos infecciosos de menor gravedad Esta disminuicion en la capacidad bactericida de los neutrofilos hallada en pacientes septicos a pesar de la estimulacion y descartada una disfuncion hereditaria del sistema fagocitario puede considerarse un defecto adquirido producido posiblemente por el mismo proceso septico


Subject(s)
Adolescent , Adult , Middle Aged , Aged , Humans , Male , Female , Bacterial Infections , Neutrophils , Nitroblue Tetrazolium , Sepsis
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