RESUMEN
BACKGROUND: Partial or an entire deletion of SHANK3 are considered as major drivers in the Phelan-McDermid syndrome, in which 75% of patients are diagnosed with autism spectrum disorder (ASD). During the recent years, there was an increasing interest in stem cell therapy in ASD, and specifically, mesenchymal stem cells (MSC). Moreover, it has been suggested that the therapeutic effect of the MSC is mediated mainly via the secretion of small extracellular vesicle that contains important molecular information of the cell and are used for cell-to-cell communication. Within the fraction of the extracellular vesicles, exosomes were highlighted as the most effective ones to convey the therapeutic effect. METHODS: Exosomes derived from MSC (MSC-exo) were purified, characterized, and given via intranasal administration to Shank3B KO mice (in the concentration of 107 particles/ml). Three weeks post treatment, the mice were tested for behavioral scoring, and their results were compared with saline-treated control and their wild-type littermates. RESULTS: Intranasal treatment with MSC-exo improves the social behavior deficit in multiple paradigms, increases vocalization, and reduces repetitive behaviors. We also observed an increase of GABARB1 in the prefrontal cortex. CONCLUSIONS: Herein, we hypothesized that MSC-exo would have a direct beneficial effect on the behavioral autistic-like phenotype of the genetically modified Shank3B KO mouse model of autism. Taken together, our data indicate that intranasal treatment with MSC-exo improves the core ASD-like deficits of this mouse model of autism and therefore has the potential to treat ASD patients carrying the Shank3 mutation.
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Trastorno Autístico/genética , Trastorno Autístico/terapia , Exosomas/metabolismo , Células Madre Mesenquimatosas/metabolismo , Proteínas de Microfilamentos/genética , Proteínas del Tejido Nervioso/genética , Administración Intranasal , Animales , Conducta Animal , Barrera Hematoencefálica/patología , Encéfalo/patología , Modelos Animales de Enfermedad , Masculino , Ratones Noqueados , Fenotipo , Conducta Social , Ácido gamma-Aminobutírico/metabolismoRESUMEN
CD44 is a cell surface adhesion molecule and its principal ligand is hyaluronic acid (HA), a key component of the brain's extracellular matrix. CD44 levels are decreased in the cerebrospinal fluid (CSF) of depressed individuals, and the CD44 gene has been identified in genome wide association study as a possible risk gene in suicidal behavior. In order to define the pathobiological mechanisms by which CD44 may affect behavior, we investigated the role of CD44 using male CD44 knockout (CD44KO) and wild-type mice that underwent chronic mild stress (CMS). Behavior was characterized using the sucrose preference and forced swim tests, open field, novel object recognition, social preference, and the elevated plus maze tests. Gene expression in hippocampus was evaluated using quantitative real-time PCR. Brain monoamines and their metabolites were assessed by high-performance liquid chromatography and serum HA and IL-1ß levels were measured using ELISA and electrochemiluminescence assays. CD44KO mice were more susceptible to stress-induced anxiety-like behavior and displayed increased anhedonia and despair than the wild-type controls. The behavioral phenotype of stressed CD44KO mice was associated with reduced cortical serotonergic and striatal dopaminergic turnover. The hippocampal expression of the receptor for HA-mediated motility (RHAMM) was reduced in the non- stressed CD44KO mice compared with WT mice, in a value similar to that observed in WT mice following exposure to stress. Taken together, our experiments suggest that CD44 plays a key role in stress response in mice.
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Ansiedad/genética , Receptores de Hialuranos/genética , Estrés Psicológico/genética , Animales , Ansiedad/etiología , Ansiedad/metabolismo , Dopamina/metabolismo , Eliminación de Gen , Hipocampo/metabolismo , Hipocampo/fisiología , Ácido Hialurónico/sangre , Interleucina-1beta/sangre , Masculino , Ratones , Ratones Endogámicos DBA , Fenotipo , Serotonina/metabolismo , Estrés Psicológico/complicaciones , Estrés Psicológico/metabolismoRESUMEN
BACKGROUND: The glycosaminoglycan hyaluronic acid (HA) is an important component of the extracellular matrix (ECM) in the brain. CD44 is a cell adhesion molecule that binds to HA in the ECM and is present on astrocytes, microglia and certain neurons. Cell adhesion molecules have been reported to be involved in anxiety and mood disorders. CD44 levels are decreased in the cerebrospinal fluid (CSF) of depressed individuals, and the CD44 gene has been identified in brain GWAS studies as a possible risk gene for suicidal behavior. METHOD: We measured the CSF levels of HA and the soluble CD44 (sCD44) in suicide attempters (n=94) and in healthy controls (n=45) using ELISA and electrochemiluminescence assays. We also investigated other proteins known to interact with CD44, such as osteopontin and the matrix metalloproteinases MMP1, MMP3 and MMP9. RESULTS: The suicide attempters had higher CSF levels of HA (p=.003) and MMP9 (p=.004). The CSF levels of HA correlated with BBB-permeability (rho=0.410, p<.001) and MMP9 correlated with sCD44 levels (rho=0.260, p=.005). LIMITATIONS: Other relevant biological contributors to suicidal behavior is not addressed in parallel to the specific role of CD44-HA signaling. The gender distribution of the patients from whom CSF was analyzed was uneven. CONCLUSIONS: Increased BBB-permeability and HA levels might be a results of increased neuroinflammation and can play a role in the pathobiology of suicidal behavior. The CD44 signaling pathway might be considered a novel target for intervention in mood disorders.
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Barrera Hematoencefálica/metabolismo , Receptores de Hialuranos/líquido cefalorraquídeo , Receptores de Hialuranos/metabolismo , Ácido Hialurónico/líquido cefalorraquídeo , Ácido Hialurónico/metabolismo , Intento de Suicidio , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Metaloproteinasa 1 de la Matriz/líquido cefalorraquídeo , Metaloproteinasa 3 de la Matriz/líquido cefalorraquídeo , Metaloproteinasa 9 de la Matriz/líquido cefalorraquídeo , Osteopontina/líquido cefalorraquídeo , PermeabilidadRESUMEN
Neurotrophic factors (NTFs) are essential growth factor proteins that support the development, survival, and proper function of neurons. We have developed muscle progenitor cell (MPC) populations expressing brain-derived neurotrophic factor (BDNF), glial-derived neurotrophic factor (GDNF), vascular endothelial growth factor (VEGF), or insulin-like growth factor-1 (IGF-1). Transplantation of a mixture of such MPC populations (MPC-MIX) into the hind legs of SOD1 G93A transgenic mice (SOD1 mice), the commonly used model of ALS, delayed the onset of disease symptoms by 30 days and prolonged the average lifespan by 13 days. Treated mice also showed a decrease in the degeneration of neuromuscular junction and an increase in axonal survival. Cellular mechanism assays suggest a synergistic rescue effect of NTFs that involves the AKT and BAD signaling pathways. The results suggest that long-term delivery of a mixture of several NTFs by the transplantation of engineered MPC has a beneficial effect in the ALS mouse model.
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Esclerosis Amiotrófica Lateral/terapia , Mioblastos/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Animales , Femenino , Masculino , Ratones , Mioblastos/trasplante , Factores de Crecimiento Nervioso/genética , Unión Neuromuscular/metabolismo , Unión Neuromuscular/patología , Superóxido Dismutasa/genética , Superóxido Dismutasa-1RESUMEN
Huntington's disease (HD) is a hereditary, progressive and ultimately fatal neurodegenerative disorder. Excitotoxicity and reduced availability of neurotrophic factors (NTFs) likely play roles in HD pathogenesis. Recently we developed a protocol that induces adult human bone marrow derived mesenchymal stem cells (MSCs) into becoming NTF secreting cells (NTF(+) cells). Striatal transplantation of such cells represents a promising autologous therapeutic approach whereby NTFs are delivered to damaged areas. Here, the efficacy of NTF(+) cells was evaluated using the quinolinic acid (QA) rat model for excitotoxicity. We show that NTF(+) cells transplanted into rat brains after QA injection survive transplantation (19% after 6 weeks), maintain their NTF secreting phenotype and significantly reduce striatal volume changes associated with QA lesions. Moreover, QA-injected rats treated with NTF(+) cells exhibit improved behavior; namely, perform 80% fewer apomorphine induced rotations than PBS-treated QA-injected rats. Importantly, we found that MSCs derived from HD patients can be induced to become NTF(+) cells and exert efficacious effects similarly to NTF(+) cells derived from healthy donors. To our knowledge, this is the first study to take adult bone marrow derived mesenchymal stem cells from patients with an inherited disease, transplant them into an animal model and evidence therapeutic benefit. Using MRI we demonstrate in vivo that PBS-treated QA-injected striatae exhibit increasing T(2) values over time in lesioned regions, whereas T(2) values decrease in equivalent regions of QA-injected rats treated with NTF(+) cells. We conclude that NTF cellular treatment could serve as a novel therapy for managing HD.
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Cuerpo Estriado/patología , Enfermedad de Huntington/patología , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Animales , Diferenciación Celular , Células Cultivadas , Modelos Animales de Enfermedad , Humanos , Células Madre Mesenquimatosas/patología , Ácido Quinolínico , RatasRESUMEN
Sciatic nerve injury may cause neurological deficits, particularly muscle weakness. Previous studies have shown that administration of neurotrophic factors (NTFs), naturally occurring proteins that support the development and survival of neurons, partially protected the damaged motor neuron in the injured sciatic nerve. In the current study, we have examined whether the administration of various combinations of transfected muscle progenitor cells (MPCs) populations, each expressing a single NTF (BDNF, GDNF, IGF-1 or VEGF) or conditioned media of such culture are capable of rescuing motor neurons in culture or in vivo. We have found that the mixture of conditioned media collected from cultured myogenic cells (MPCs- MIX(+)) alleviated the toxic effect of exposure of the motor neuron cell line NSC34 to hypoxic environment. Furthermore, NTFs secreting cells transplantation, protected motor neurons in a unilateral rat sciatic nerve injury model: One day after the crush, rats underwent transplantation at the lesion site with rat myogenic cells expressing one of the four NTFs; a mixture of cells expressing all four NTFs (MPCs- MIX(+)), MPCs-GFP or PBS. We found that in rats injected with MPCs- MIX(+) the motor function was markedly preserved, compared to groups injected with cells secreting a single NTF, GFP or PBS. Transplantation of the MPCs- MIX(+) significantly inhibited the degeneration of the neuromuscular junctions and enhanced the survival of the myelinated motor axons. The injection of MPCs- MIX(+) preserved the compound muscle action potential (CMAP) as was demonstrated by motor nerve conduction studies. Our findings suggest that MPCs induced to secrete several NTFs can synergistically alleviate symptoms of sciatic nerve injury and perhaps other motor neuron disorders..
RESUMEN
Stem cell-based regenerative therapy is considered a promising cellular therapeutic approach for the patients with incurable brain diseases. Mesenchymal stem cells (MSCs) represent an attractive cell source for regenerative medicine strategies for the treatment of the diseased brain. Previous studies have shown that these cells improve behavioral deficits in animal models of neurological disorders such as Parkinson's and Huntington's diseases. In the current study, we examined the capability of intracerebral human MSCs transplantation (medial pre-frontal cortex) to prevent the social impairment displayed by mice after withdrawal from daily phencyclidine (PCP) administration (10 mg kg(-1) daily for 14 days). Our results show that MSCs transplantation significantly prevented the PCP-induced social deficit, as assessed by the social preference test. In contrast, the PCP-induced social impairment was not modified by daily clozapine treatment. Tissue analysis revealed that the human MSCs survived in the mouse brain throughout the course of the experiment (23 days). Significantly increased cortical brain-derived neurotrophic factor levels were observed in the MSCs-treated group as compared with sham-operated controls. Furthermore, western blot analysis revealed that the ratio of phosphorylated Akt to Akt was significantly elevated in the MSCs-treated mice compared with the sham controls. Our results demonstrate that intracerebral transplantation of MSCs is beneficial in attenuating the social deficits induced by sub-chronic PCP administration. We suggest a novel therapeutic approach for the treatment of schizophrenia-like negative symptoms in animal models of the disorder.
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Células Madre Adultas/trasplante , Conducta Animal/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/biosíntesis , Trasplante de Células Madre Mesenquimatosas , Conducta Social , Regulación hacia Arriba/fisiología , Animales , Conducta Animal/fisiología , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Factor Neurotrófico Derivado del Encéfalo/fisiología , Clozapina/uso terapéutico , Modelos Animales de Enfermedad , Humanos , Trasplante de Células Madre Mesenquimatosas/métodos , Ratones , Fenciclidina/toxicidad , Corteza Prefrontal/trasplante , Regulación hacia Arriba/efectos de los fármacosRESUMEN
PURPOSE: To characterize the histological changes that occur in response to induction of ischemic or mechanical optic nerve damage in transgenic mice. METHODS: Either optic nerve crush injury or rodent anterior ischemic optic neuropathy (rAION) were induced in the right eye of mice transgenic for the Thy1 gene promoter expressing cyan fluorescent protein (CFP; n=40) and mice transgenic for the cyclic nucleotide phosphodiesterase (CNPase) gene promoter expressing green fluorescent protein (GFP; n=40). The left eye served as a control. The mice were euthanized at different times after injury. Eyes were enucleated, and the brain together with the optic nerves was completely dissected. Cryopreserved sections of both optic nerves were analyzed by fluorescence microscopy. In addition, flat-mounted retinas from the Thy1-CFP mice were analyzed for retinal ganglion cell (RGC) loss. RESULTS: Axonal loss was detected in the right eye of the Thy1-CFP mice, and demyelination was detected in the CNPase-GFP mice. Both processes occurred simultaneously in the two models of injury. The damage proceeded retrogradely and, in the crush-injury group, crossed the chiasm within 4 days. At 21 days after injury, RGC loss measured 70% in the crush-injury group and 25% in the rAION group. CONCLUSIONS: Axonal injury and demyelination along the optic nerves occur simultaneously in transgenic mice exposed to ischemic or crush injury. The degree of RGC loss reflects the severity of the injury. Loss of oligodendrocytes and myelin apparently leads to axonal loss. Transgenic mice offer a promising model for exploring the damage caused by optic nerve injury. Use of fluorescence labeling makes it possible to better understand the underlying pathophysiology, which can help researchers formulate neuroprotective agents.
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Modelos Animales de Enfermedad , Traumatismos del Nervio Óptico/patología , Nervio Óptico/patología , Neuropatía Óptica Isquémica/patología , 2',3'-Nucleótido Cíclico Fosfodiesterasas/metabolismo , Animales , Apoptosis , Axones/patología , Proteínas Fluorescentes Verdes/metabolismo , Etiquetado Corte-Fin in Situ , Ratones , Ratones Transgénicos , Oligodendroglía/patología , Quiasma Óptico/patología , Nervio Óptico/metabolismo , Traumatismos del Nervio Óptico/inducido químicamente , Traumatismos del Nervio Óptico/metabolismo , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/patología , Antígenos Thy-1/metabolismoRESUMEN
BACKGROUND: Human bone marrow multipotent mesenchymal stromal cells (hMSC), because of their capacity of multipotency, may provide an unlimited cell source for cell replacement therapy. The purpose of this study was to assess the developmental potential of hMSC to replace the midbrain dopamine neurons selectively lost in Parkinson's disease. METHODS: Cells were isolated and characterized, then induced to differentiate toward the neural lineage. In vitro analysis of neural differentiation was achieved using various methods to evaluate the expression of neural and dopaminergic genes and proteins. Neural-induced cells were then transplanted into the striata of hemi-Parkinsonian rats; animals were tested for rotational behavior and, after killing, immunohistochemistry was performed. RESULTS: Following differentiation, cells displayed neuronal morphology and were found to express neural genes and proteins. Furthermore, some of the cells exhibited gene and protein profiles typical of dopaminergic precursors. Finally, transplantation of neural-induced cells into the striatum of hemi-Parkinsonian rats resulted in improvement of their behavioral deficits, as determined by apomorphine-induced rotational behavior. The transplanted induced cells proved to be of superior benefit compared with the transplantation of naive hMSC. Immunohistochemical analysis of grafted brains revealed that abundant induced cells survived the grafts and some displayed dopaminergic traits. DISCUSSION: Our results demonstrate that induced neural hMSC may serve as a new cell source for the treatment of neurodegenerative diseases and have potential for broad application. These results encourage further developments of the possible use of hMSC in the treatment of Parkinson's disease.
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Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/fisiología , Regeneración Nerviosa/fisiología , Neuronas/fisiología , Enfermedad de Parkinson/terapia , Células del Estroma/fisiología , Adulto , Anciano , Animales , Conducta Animal/fisiología , Diferenciación Celular , Linaje de la Célula , Movimiento Celular , Forma de la Célula , Supervivencia Celular , Células Cultivadas , Medios de Cultivo/química , Modelos Animales de Enfermedad , Dopamina/metabolismo , Humanos , Masculino , Células Madre Mesenquimatosas/citología , Persona de Mediana Edad , Neuronas/citología , Enfermedad de Parkinson/patología , Ratas , Ratas Sprague-Dawley , Células del Estroma/citologíaRESUMEN
Strategies of cell therapy for the treatment of Parkinson's disease (PD) are focused on replacing damaged neurons with cells to restore or improve function that is impaired due to cell population damage. In our studies, we used mesenchymal stromal cells (MSCs) from mouse bone marrow. Following our novel neuronal differentiation method, we found that the basic cellular phenotype changed to cells with neural morphology that express specific markers including those characteristic for dopaminergic neurons, such as tyrosine hydroxylase (TH). Intrastriatal transplantation of the differentiated MSCs in 6-hydroxydopamine-lesioned mice led to marked reduction in the amphetamine-induced rotations. Immunohistological analysis of the mice brains four months post transplantation, demonstrated that most of the transplanted cells survived in the striatum and expressed TH. Some of the TH positive cells migrated toward the substantia nigra. In conclusion, transplantation of bone marrow derived stem cells differentiated to dopaminergic-like cells, successfully improved behavior in an animal model of PD suggesting an accessible source of cells that may be used for autotransplantation in patient with PD.
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Trasplante de Médula Ósea , Cuerpo Estriado/cirugía , Trasplante de Células Madre Mesenquimatosas , Actividad Motora/fisiología , Trastornos Parkinsonianos/cirugía , Anfetamina/farmacología , Animales , Western Blotting , Diferenciación Celular/fisiología , Movimiento Celular/fisiología , Supervivencia Celular/fisiología , Cuerpo Estriado/patología , Cuerpo Estriado/fisiopatología , Dopamina/metabolismo , Proteínas Fluorescentes Verdes/genética , Procesamiento de Imagen Asistido por Computador , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microscopía Fluorescente , Neuronas/patología , Neuronas/fisiología , Trastornos Parkinsonianos/patología , Trastornos Parkinsonianos/fisiopatología , Conducta Estereotipada/efectos de los fármacos , Conducta Estereotipada/fisiología , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
Neurodegenerative diseases are characterized by a progressive degeneration of selective neural populations. This selective hallmark pathology and the lack of effective treatment modalities make these diseases appropriate candidates for cell therapy. Bone marrow-derived mesenchymal stem cells (MSCs) are self-renewing precursors that reside in the bone marrow and may further be exploited for autologous transplantation. Autologous transplantation of MSCs entirely circumvents the problem of immune rejection, does not cause the formation of teratomas, and raises very few ethical or political concerns. More than a few studies showed that transplantation of MSCs resulted in clinical improvement. However, the exact mechanisms responsible for the beneficial outcome have yet to be defined. Possible rationalizations include cell replacement, trophic factors delivery, and immunomodulation. Cell replacement theory is based on the idea that replacement of degenerated neural cells with alternative functioning cells induces long-lasting clinical improvement. It is reasoned that the transplanted cells survive, integrate into the endogenous neural network, and lead to functional improvement. Trophic factor delivery presents a more practical short-term approach. According to this approach, MSC effectiveness may be credited to the production of neurotrophic factors that support neuronal cell survival, induce endogenous cell proliferation, and promote nerve fiber regeneration at sites of injury. The third potential mechanism of action is supported by the recent reports claiming that neuroinflammatory mechanisms play an important role in the pathogenesis of neurodegenerative disorders. Thus, inhibiting chronic inflammatory stress might explain the beneficial effects induced by MSC transplantation. Here, we assemble evidence that supports each theory and review the latest studies that have placed MSC transplantation into the spotlight of biomedical research.
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Células de la Médula Ósea/citología , Enfermedades Neurodegenerativas/terapia , Trasplante de Células Madre/métodos , Encéfalo/inmunología , Factor Neurotrófico Derivado de la Línea Celular Glial/fisiología , Trasplante de Células Madre Hematopoyéticas , Humanos , Trasplante de Células Madre Mesenquimatosas , Enfermedades Neurodegenerativas/inmunología , Trasplante AutólogoRESUMEN
We have previously found that, following myocardial ischemia/reperfusion injury, isolated hearts from bax gene knockout mice [Bax(-/-)] exhibited higher cardioprotection than the wild-type. We here explore the effect of Bax(-/-), following myocardial infarction (MI) in vivo. Homozygotic Bax(-/-) and matched wild-type were studied. Mice underwent surgical ligation of the left anterior descending coronary artery (LAD). The progressive increase in left-ventricular end diastolic diameter, end systolic diameter, in Bax(-/-) was significantly smaller than in Bax(+/+) at 28 d following MI (p < 0.03) as seen by echocardiography. Concomitantly, fractional shortening was higher (35 +/- 4.1% and 27 +/- 2.5%, p < 0.001) and infarct size was smaller in Bax(-/-) compared to the wild-type at 28 days following MI (24 +/- 3.7 % and 37 +/- 3.3%, p < 0.001). Creatine kinase and lactate dehydrogenase release in serum were lower in Bax(-/-) than in Bax(+/+) 24 h following MI. Caspase 3 activity was elevated at 2 h after MI only in the wild-type, but reduced to baseline values at 1 and 28 d post-MI. Bax knockout mice hearts demonstrated reduced infarct size and improved myocardial function following permanent coronary artery occlusion. The Bax gene appears to play a significant role in the post-MI response that should be further investigated.
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Infarto del Miocardio/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Animales , Apoptosis , Peso Corporal , Caspasas/metabolismo , Ecocardiografía/métodos , Femenino , Heterocigoto , Homocigoto , Masculino , Ratones , Ratones Noqueados , Infarto del Miocardio/genética , Infarto del Miocardio/patología , Miocardio/patología , Factores de TiempoRESUMEN
Parkinson's disease is characterized by the loss of dopaminergic neurons in the substantia nigra. Attempted replacement of these neurons by stem cells has proved inconclusive. Bone marrow mesenchymal stem cells (MSC) are multipotent, differentiating into a variety of cells, including neuron-like cells. We used the 6-hydroxydopamine (6-OHDA) animal model of Parkinson's disease to assess migration and differentiation of transplanted MSC. We found in rodents that transplanted MSC survive better in the 6-OHDA-induced damaged hemisphere compared to the unlesioned side. Moreover, contralaterally engrafted MSC migrated through the corpus callosum to populate the striatum, thalamic nuclei and substantia nigra of the 6-OHDA-lesioned hemisphere. In conclusion, we demonstrate that 6-OHDA-induced damage increases the viability of transplanted MSC and attracts these cells from the opposite hemisphere.
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Trasplante de Médula Ósea , Diferenciación Celular/fisiología , Movimiento Celular/fisiología , Trasplante de Células Madre Mesenquimatosas , Trastornos Parkinsonianos/terapia , Animales , Supervivencia Celular , Ratones , Ratas , Células Madre/citologíaRESUMEN
Bone marrow derived mesenchymal stem cells (MSC) are adult stem cells that reside within the bone marrow compartment. In the traditional developmental model, adult stem cells are able to differentiate only to the tissue in which they reside. Recent data have challenged the committed fate of the adult stem cells, presenting evidence for their multi-lineage differentiation potential. In addition, potential therapeutic benefits of MSC administration have been the main concern of much research, including clinical trials. These studies promote adult stem cell therapy by shedding some light on the therapeutic potential of MSC and their mechanism of action. Many doubts have found their way into MSC research. They question MSC potency and beneficial contribution. However, these obstacles should not arrest but set a challenge to MSC researchers to examine their achievements under a magnifying glass. Therapeutic benefits of MSC exogenous delivery do not run counter to its possible participation in endogenous repair. Several reports imply MSC involvement in physiological repair but no explicit data support this hypothesis. This review tries to put MSC research into perspective. Possible therapeutic applications of MSC therapy for damaged tissue replacement, tissue engineering and the underlying repair mechanisms will be discussed. In addition, reported data about MSC possible involvement in physiological multiple tissue repair, their homing to injury and site-specific differentiation will be presented.
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Trasplante de Médula Ósea/métodos , Trasplante de Médula Ósea/tendencias , Trasplante de Células Madre Mesenquimatosas/métodos , Trasplante de Células Madre Mesenquimatosas/tendencias , Animales , Trasplante de Médula Ósea/patología , Ensayos Clínicos como Asunto , Predicción , HumanosRESUMEN
Idiopathic Parkinson's disease (IPD) is a progressive neurodegenerative disorder for which no restorative or neuroprotective therapy is available. Interest has recently been directed to association studies on polymorphisms of various genes, mainly those related to dopamine metabolism and transport, and their effect on response to PD, which includes primarily levodopa and dopaminomimetics. Approximately 15-20% of patients with PD do not respond to levodopa, and the majority of those who do respond develop adverse fluctuations in motor response, primarily levodopa-induced dyskinesias. This review summarizes the influence of polymorphisms in various genes on the relative risk of IPD and on levodopa efficacy. It focuses on the importance of well-designed polymorphism studies that include large samples of patients with IPD and tightly matched controls and use identical methodologies. Valid data on such polymorphisms might increase the efficacy of levodopa, decrease its side effects, and reduce the occurrence of levodopa-induced dyskinesias. They might also provide a novel diagnostic tool for PD.
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Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/genética , Polimorfismo Genético/genética , Humanos , Enfermedad de Parkinson/enzimología , Factores de RiesgoRESUMEN
Parkinson's disease (PD) is characterized by a progressive loss of 70-80% of dopaminergic (DA) neurons in the substantia nigra. High concentrations of DA were suggested to induce oxidative stress and selective neurodegeneration. We evaluated the effect of insulin-like-growth-factor-1 (IGF-1) on DA toxicity in neuronal cultures. IGF-1 (0.5 microg/ml) suppressed cell death induced by exposure to DA (0.3 mM) after 2 and 4 days, in a rat cerebellar culture. Similarly, IGF-1 (0.5 and 1.0 microg/ml) antagonized DA (0.125 and 0.250 mM) neurotoxicity in a human neuroblastoma cell line (SK-N-SH). Flowcytometric analysis of neuroblastoma cells treated with DA (0.5 mM) showed increased apoptosis, which was significantly reduced by IGF-1. The effect of IGF-1 was associated with increased Bcl-2 expression as indicated by flowcytometry and Western blot analysis. We suggest that IGF-1 possesses a neuroprotective effect against DA-induced toxicity, and may have a potential role in the treatment of PD.
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Encéfalo/efectos de los fármacos , Dopamina/metabolismo , Factor I del Crecimiento Similar a la Insulina/farmacología , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Neurotoxinas/metabolismo , Enfermedad de Parkinson/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Encéfalo/metabolismo , Encéfalo/fisiopatología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Células Cultivadas , Corteza Cerebelosa , Dopamina/toxicidad , Relación Dosis-Respuesta a Droga , Humanos , Inmunohistoquímica , Neuroblastoma , Neuronas/metabolismo , Neurotoxinas/toxicidad , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/fisiopatología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Células Tumorales CultivadasRESUMEN
Oxidative stress (OS) has been implicated in the pathophysiology of many neurological, particularly neurodegenerative diseases. OS can cause cellular damage and subsequent cell death because the reactive oxygen species (ROS) oxidize vital cellular components such as lipids, proteins, and DNA. Moreover, the brain is exposed throughout life to excitatory amino acids (such as glutamate), whose metabolism produces ROS, thereby promoting excitotoxicity. Antioxidant defense mechanisms include removal of O(2), scavenging of reactive oxygen/nitrogen species or their precursors, inhibition of ROS formation, binding of metal ions needed for the catalysis of ROS generation and up-regulation of endogenous antioxidant defenses. However, since our endogenous antioxidant defenses are not always completely effective, and since exposure to damaging environmental factors is increasing, it seems reasonable to propose that exogenous antioxidants could be very effective in diminishing the cumulative effects of oxidative damage. Antioxidants of widely varying chemical structures have been investigated as potential therapeutic agents. However, the therapeutic use of most of these compounds is limited since they do not cross the blood brain barrier (BBB). Although a few of them have shown limited efficiency in animal models or in small clinical studies, none of the currently available antioxidants have proven efficacious in a large-scale controlled study. Therefore, any novel antioxidant molecules designed as potential neuroprotective treatment in acute or chronic neurological disorders should have the mandatory prerequisite that they can cross the BBB after systemic administration.
Asunto(s)
Antioxidantes/administración & dosificación , Barrera Hematoencefálica/efectos de los fármacos , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/fisiopatología , Estrés Oxidativo/efectos de los fármacos , Animales , Barrera Hematoencefálica/fisiología , Humanos , Enfermedades Neurodegenerativas/tratamiento farmacológico , Estrés Oxidativo/fisiologíaRESUMEN
Glutaredoxin 2 (Grx2) from Escherichia coli protects cerebellar neurons from dopamine-induced apoptosis via nuclear factor kappa B (NF-kappaB) activation, which is mediated by the expression of redox factor-1 (Ref-1). An analysis of the mechanisms underlying Grx2 protective activity revealed dual activation of signal transduction pathways. Grx2 significantly activated the Ras/phosphoinositide 3-kinase/Akt/NF-kappaB cascade in parallel to the Jun N-terminal kinase (JNK)/AP1 cascade. Dopamine, in comparison, down-regulated both pathways. Treatment of neurons with Ref-1 antisense oligonucleotide reduced the ability of Grx2 to activate Akt and AP-1 but had no effect on the phosphorylation of JNK1/2, suggesting that Akt/NF-kappaB and AP-1 are regulated by Ref-1. Exposure of the neurons to JNK1/2 antisense oligonucleotide in the presence of Grx2 significantly reduced AP-1 and NF-kappaB DNA binding activities and abolished Grx2 protection. These results demonstrate that dual activation of Ras/phosphoinositide 3-kinase and AP-1 cascades, which are mediated by Ref-1, is an essential component of the Grx2 mechanism of action.
Asunto(s)
Apoptosis/efectos de los fármacos , Cerebelo/citología , Dopamina/farmacología , Farnesol/análogos & derivados , Sistema de Señalización de MAP Quinasas/fisiología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Neuronas/efectos de los fármacos , Oxidorreductasas , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas , Proteínas/farmacología , Animales , Animales Recién Nacidos , Proteínas Bacterianas/farmacología , Células Cultivadas , Cerebelo/fisiología , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Escherichia coli , Farnesol/farmacología , Glutarredoxinas , Proteínas Quinasas JNK Activadas por Mitógenos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Modelos Neurológicos , FN-kappa B/metabolismo , Neuronas/citología , Neuronas/fisiología , Fosforilación , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-akt , Salicilatos/farmacología , Proteínas ras/metabolismoRESUMEN
The etiology of Parkinson's disease is still unknown, though current investigations support the notion of the pivotal involvement of oxidative stress in the process of neurodegeneration in the substantia nigra (SN). In the present study, we investigated the molecular mechanisms underlying cellular response to a challenge by dopamine, one of the local oxidative stressors in the SN. Based on studies showing that nuclear factor kappa B (NF-kappaB) is activated by oxidative stress, we studied the involvement of NF-kappaB in the toxicity of PC12 cells following dopamine exposure. We found that dopamine (0.1-0.5 m M) treatment increased the phosphorylation of the IkappaB protein, the inhibitory subunit of NF-kappaB in the cytoplasm. Immunoblot analysis demonstrated the presence of NF-kappaB-p65 protein in the nuclear fraction and its disappearance from the cytoplasmic fraction after 2 h of dopamine exposure. Dopamine-induced NF-kappaB activation was also evidenced by electromobility shift assay using radioactive labeled NF-kappaB consensus DNA sequence. Cell-permeable NF-kappaB inhibitor SN-50 rescued the cells from dopamine-induced apoptosis and showed the importance of NF-kappaB activation to the induction of apoptosis. Furthermore, flow cytometry assay demonstrated a higher level of translocated NF-kappaB-p65 in the apoptotic nuclei than in the unaffected nuclei. In conclusion, our findings suggest that NF-kappaB activation is essential to dopamine-induced apoptosis in PC12 cells and it may be involved in nigral neurodegeneration in patients with Parkinson's disease.
Asunto(s)
Apoptosis/efectos de los fármacos , Dopamina/farmacología , FN-kappa B/fisiología , Células PC12/efectos de los fármacos , Animales , Antioxidantes/farmacología , Caspasa 3 , Inhibidores de Caspasas , Núcleo Celular/metabolismo , Inhibidores de Cisteína Proteinasa/farmacología , Citoplasma/metabolismo , Dopamina/toxicidad , Citometría de Flujo , Proteínas I-kappa B/metabolismo , FN-kappa B/metabolismo , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/fisiología , Degeneración Nerviosa , Fármacos Neuroprotectores/farmacología , Oligopéptidos/farmacología , Estrés Oxidativo , Enfermedad de Parkinson/etiología , Enfermedad de Parkinson/metabolismo , Péptidos/farmacología , Fosforilación/efectos de los fármacos , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Ratas , Especies Reactivas de Oxígeno , Transducción de Señal/efectos de los fármacos , Factor de Transcripción ReIARESUMEN
The purpose of this study was to examine the effects of 3-O-methylation by catechol-O-methyltransferase (COMT) on the toxicity of levodopa in neuronal cultures. High concentrations of levodopa are toxic in vitro. Therefore, there is concern that long-term treatment with levodopa in patients with Parkinson's disease might accelerate the rate of degeneration of nigrostriatal neurons. However, recent studies have suggested that, while levodopa is harmful in vitro, it may not be toxic in vivo. A possible defense mechanism is by means of metabolic shunting of levodopa excess to 3-O-methyldopa by COMT in peripheral and central nervous system tissues. In this study we examine whether the use of COMT inhibitor, which reduced the levels of 3-O-methyldopa, affect levodopa toxicity. Mice cerebellar granule neurons, PC12, and neuroblastoma cells were used, and their viability following exposure to levodopa and COMT with and without tolcapone, a COMT inhibitor, was measured by neutral red staining. Auto-oxidation of levodopa was evaluated using a spectrophotometer (690 nm). We found that 3-O-methyldopa, unlike levodopa, was not toxic to all cells examined. Addition of purified COMT to levodopa prevented its auto-oxidation and markedly attenuated its cytotoxicity in vitro. Additional tolcapone reversed the protective effect of COMT. The agent 3-O-methyldopa is not toxic to cell cultures. Catechol-O-methyltransferase attenuates toxicity of levodopa in vitro by its metabolism to nontoxic 3-O-methyldopa.