Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 26
Filter
1.
Int. j. morphol ; 41(3): 825-830, jun. 2023. ilus, tab
Article in English | LILACS | ID: biblio-1514291

ABSTRACT

SUMMARY: The cerebellum is a crucial area of the hindbrain that plays an essential role in balancing, excitement control, and subtle and accurate functions. Studies have shown that long-term use of D-galactose in mice, as with the symptoms of aging, causes morphological and functional disorders in the brain. This study was performed to evaluate the changes in the cerebellum cortex tissue and the measurement of reactive oxygen species (ROS) in the cerebellum following the induction of aging in mice by D-galactose. Accordingly, subjects were randomly assigned into two groups: Normal saline group and Aging group (D-galactose). To create an aging model, D- galactose, and saline solution (sodium chloride 0.9 %) were used. After completing the preparation and passage of the tissue, the cerebellum specimens were cut in 5 microns thickness and then stained with hematoxylin-eosin stain and finally examined under a Nikon microscope. Quantitative variables were analyzed by SPSS software using T-test. In the observations of cerebellum tissue samples, in the aged induced group by D-galactose, the most changes were observed in the Neuron purkinjense (Purkinje cells) layer. In the observations of the cerebellum tissue samples of aging group induced by D-galactose, the most changes were observed in the Neuron purkinjense, and the arrangement and placement of these cells were disorientated. The nucleus positioning was not central, and the Neuron purkinjense induced by aging were seen in different morphological forms. Necrosis, Chromatolysis, and Pyknosis were found. Based on the results, D-galactose (induction of aging) causes pathological changes in the cerebellar cortex, especially in the Neuron purkinjense layer.


El cerebelo es un área crucial del rombencéfalo que desempeña un papel esencial en el equilibrio, el control de la excitación y las funciones sutiles y precisas. Los estudios han demostrado que el uso a largo plazo de D-galactosa en ratones, al igual que con los síntomas del envejecimiento, provoca trastornos morfológicos y funcionales en el cerebro. Este estudio se realizó para evaluar los cambios en el tejido de la corteza del cerebelo y la medición de especies reactivas de oxígeno (ROS) en el cerebelo luego de la inducción del envejecimiento en ratones por D-galactosa. En consecuencia, los sujetos fueron asignados aleatoriamente a dos grupos: grupo de solución salina normal y grupo de envejecimiento (D-galactosa). Para crear un modelo de envejecimiento, se utilizaron D-galactosa y solución salina (cloruro de sodio al 0,9 %). Después de completar la preparación y el paso del tejido, las muestras de cerebelo se cortaron en un grosor de 5 µm y luego se tiñeron con tinción de hematoxilina-eosina y finalmente se examinaron bajo un microscopio Nikon. Las variables cuantitativas se analizaron mediante el software SPSS utilizando la prueba T. En las observaciones de muestras de tejido de cerebelo, en el grupo envejecido inducido por D-galactosa, la mayoría de los cambios se observaron en la capa de neuronas purkinjenses (células de Purkinje). En las observaciones de las muestras de tejido del cerebelo del grupo de envejecimiento inducidas por D-galactosa, la mayoría de los cambios se observaron en las neuronas purkinjenses, y la disposición y ubicación de estas células estaban desorientadas. El posicionamiento del núcleo no era central y las neuronas purkinjenses inducidas por el envejecimiento se observaban en diferentes formas morfológicas. Se encontró necrosis, cromatólisis y picnosis. Según los resultados, la D-galactosa (inducción del envejecimiento) provoca cambios patológicos en la corteza cerebelosa, especialmente en la capa de neuronas purkinjenses.


Subject(s)
Animals , Male , Mice , Aging , Cerebellum/pathology , Galactose/administration & dosage , Purkinje Cells , Cerebellum/cytology , Reactive Oxygen Species , Models, Animal , Mice, Inbred BALB C
3.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 68(10): 1383-1388, Oct. 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1406554

ABSTRACT

SUMMARY OBJECTIVE: The aim of this study was to examine the changes on the Purkinje cells in the cerebella of male rat pups born to pregnant dams that were exposed to an electromagnetic field in the prenatal period. METHODS: The first stage of the study involved 12 Sprague-Dawley rats, 6 male and 6 female, weighing between 180 and 250 g. The female rats in the experimental group were exposed to a 900-MHz electromagnetic field for 1 h at the same time every day, and no procedure was performed on the control group. Following pregnancy, six male pups from each group were divided into experimental and control groups without any procedure on the pups. After 2 months, they were sacrificed and their cerebella were removed. Histopathologically, following routine processing and fixation procedures, the cerebella were embedded in the tissue blocks. The sections taken from these blocks were stained with cresyl violet. The Purkinje cells in the cerebella were then counted on sections using the optical dissector method on an image analysis system. RESULTS: The estimation of number of the Purkinje cells in the groups revealed more cells in rats in the control group than in the experimental group. Histopathologically, Purkinje cells exhibited a normal morphological structure in the control group, while the cells in the experimental group showed damage. CONCLUSIONS: It might be asserted that the exposure of mothers to an electromagnetic field in the prenatal period may affect the development of Purkinje cells in the pup cerebella.

4.
Int. j. morphol ; 39(1): 318-326, feb. 2021. ilus
Article in English | LILACS | ID: biblio-1385294

ABSTRACT

SUMMARY: In this study the consequences of prenatal exposure to tobacco smokes on the histo-morphological changes of cerebellum was assessed by comparing the smoker mice to the nonsmoker mice. A total of 30 pregnant cd-1 mice were divided into three groups of 10 mice each and with two replicates per group (5 mice each). Following acclimation for five days, the mice were placed in a special modified smoking machine for 2 hours per day over a two- and three-week period for group two and group three, respectively. Group one was considered as a control group. Mice in the control group were exposed simultaneously to fresh air from the room, while those in the treatment groups were exposed to tobacco smoke from six commercial filter cigarettes, containing 0.8 mg of nicotine, 10 mg of tar, and 10 mg of carbon monoxide, for three 1-hour exposure periods every day for three weeks. The mice in the control group were exposed to room air for three 1-hour periods every day for the same period of three weeks. The results from this study showed a correlation between maternal smoking and histological changes in Neuron purkinjense (Purkinje cells) of the cerebellum. They also showed that prenatal smoking period may have caused more damage in the histology and structure of Neuron purkinjense in some juvenile mice. An increased incidence of morphology damage of the cerebellum's Neuron purkinjense' structures was also observed in fetuses with prolonged exposure to tobacco smoking. Exposure of in utero maternal smoking may interfere with brain biological development parameters, giving rise to structural abnormalities of the cerebellum. This study concluded that tobacco smoke exposure to pregnant mice may affect neurodevelopment which may induce behavioural changes as a result of reduced cerebellar size and function.


RESUMEN: Se evaluaron los efectos producidos por la exposición prenatal al humo de tabaco en ratones expuestos y no expuestos y los cambios histomorfológicos observados en el cerebelo en ambos grupos. Un total de 30 ratones cd-1 preñados se dividieron en tres grupos de 10 ratones cada uno y con dos réplicas por grupo (5 ratones cada uno). Después de la aclimatación durante cinco días, los ratones se colocaron en una máquina de fumar modificada, especial durante 2 horas al día, durante un período de dos y tres semanas para el grupo dos y el grupo tres, respectivamente. El grupo uno se consideró como grupo control. Los ratones del grupo de control fueron expuestos simultáneamente al aire limpio de la habitación, mientras que los grupos de tratamiento fueron expuestos al humo de tabaco de seis cigarrillos comerciales, que contenían 0,8 mg de nicotina, 10 mg de alquitrán y 10 mg de monóxido de carbono. durante tres períodos de 1 hora diariamente, durante tres semanas. Los ratones del grupo de control se expusieron al aire ambiente durante tres períodos de 1 hora todos los días durante el mismo período de tres semanas. Los resultados de este estudio mostraron una correlación entre el tabaquismo materno y los cambios histológicos en las neuronas purkinjenses (células de Purkinje). Se observó además que el período de tabaquismo prenatal puede haber causado mayor daño en la histología y estructura de las neuronas purkinjenses en algunos ratones jóvenes. También se observó una mayor incidencia de daño morfológico de las estructuras de las neuronas purkinjenses del cerebelo en fetos con exposición prolongada al tabaquismo. La exposición al tabaquismo materno en el útero puede interferir con los parámetros de desarrollo biológico del cerebro, dando lugar a anomalías estructurales del cerebelo. Este estudio concluyó que la exposición al humo del tabaco en ratones preñados puede afectar el desarrollo neurológico, lo que puede inducir cambios de comportamiento como resultado de la reducción del tamaño y la función del cerebelo.


Subject(s)
Animals , Female , Pregnancy , Tobacco Smoke Pollution/adverse effects , Cerebellum/drug effects , Prenatal Exposure Delayed Effects , Purkinje Cells/drug effects , Maternal Exposure/adverse effects
5.
Neurology Asia ; : 387-394, 2020.
Article in English | WPRIM | ID: wpr-877274

ABSTRACT

@#Ca2+ leak via ryanodine receptor type 2 (RyR2) can cause potentially fatal arrhythmias, and RyR2 mutations have been shown in the aetiology of catecholaminergic polymorphic ventricular tachycardia. We report the case of a patient with catecholaminergic polymorphic ventricular tachycardia resulting from a RYR2 mutation who had not only typical electroencephalogram changes, but also epileptiform discharges in electroencephalogram. We believe the changes were closely related to the RYR2 mutation.

6.
Rev. bras. neurol ; 55(4): 13-17, out.-dez. 2019. ilus
Article in English | LILACS | ID: biblio-1095496

ABSTRACT

Jan Evangelista Purkinje was a Czech physician with an exceptional capacity for innovative thinking, and he was one of the fathers of experimental physiology, experimental pharmacology, experimental psychology, histology, embryology, and physical anthropology. Several achievements are named after him, from his prodigious productivity. Of special interest of this paper was his pioneering role in the rise of experimental physiology, microscopical anatomy, and histological methods by the 1830´s that allowed him define more accurate data concerning the structure of nerve tissue of animals and humans such as the now known "Purkinje's cells" and others cells of the brain. He investigated the structure of neuronal processes, including the dendrites. Purkinje recognized possible functional differences between a variety of types of neurons and speculated about their interrelations. He was one of the great geniuses of science.


Jan Evangelista Purkinje foi um médico checo com excepcional capacidade de pensamento inovador e um dos pais da fisiologia experimental, farmacologia experimental, psicologia experimental, histologia, embriologia e antropologia física. Várias conquistas receberam o nome dele, de sua produtividade prodigiosa. De interesse especial deste trabalho enaltece-se o seu papel pioneiro no surgimento da fisiologia experimental, anatomia microscópica e métodos histológicos na década de 1830. Isso permitiu que ele definisse dados mais precisos sobre a estrutura do tecido nervoso de animais e humanos, como as agora conhecidas "células de Purkinje" e outras células do cérebro. Ele investigou a estrutura dos processos neuronais, incluindo os dendritos. Purkinje reconheceu possíveis diferenças funcionais entre uma variedade de tipos de neurônios e especulou sobre suas inter-relações. Ele foi um dos grandes gênios da ciência.


Subject(s)
Humans , History, 19th Century , Physicians/history , Physiology/history , Purkinje Cells/cytology , Dendrites , Nerve Tissue , Ophthalmology/history , Czech Republic , Anatomy/history
7.
Experimental Neurobiology ; : 139-154, 2018.
Article in English | WPRIM | ID: wpr-714913

ABSTRACT

What is memory? How does the brain process the sensory information and modify an organism's behavior? Many neuroscientists have focused on the activity- and experience-dependent modifications of synaptic functions in order to solve these fundamental questions in neuroscience. Recently, the plasticity of intrinsic excitability (called intrinsic plasticity) has emerged as an important element for information processing and storage in the brain. As the cerebellar Purkinje cells are the sole output neurons in the cerebellar cortex and the information is conveyed from a neuron to its relay neurons by forms of action potential firing, the modulation of the intrinsic firing activity may play a critical role in the cerebellar learning. Many voltage-gated and/or Ca²⁺-activated ion channels are involved in shaping the spiking output as well as integrating synaptic inputs to finely tune the cerebellar output. Recent studies suggested that the modulation of the intrinsic excitability and its plasticity in the cerebellar Purkinje cells might function as an integrator for information processing and memory formation. Moreover, the intrinsic plasticity might also determine the strength of connectivity to the sub-cortical areas such as deep cerebellar nuclei and vestibular nuclei to trigger the consolidation of the cerebellar-dependent memory by transferring the information.


Subject(s)
Action Potentials , Electronic Data Processing , Brain , Cerebellar Cortex , Cerebellar Nuclei , Cerebellum , Fires , Ion Channels , Learning , Memory , Neuronal Plasticity , Neurons , Neurosciences , Plastics , Purkinje Cells , Vestibular Nuclei
8.
Clinical Psychopharmacology and Neuroscience ; : 176-183, 2018.
Article in English | WPRIM | ID: wpr-714653

ABSTRACT

OBJECTIVE: Propofol is an intravenously administered anesthetic that enhances γ-aminobutyric acid-mediated inhibition in the central nerve system. Other mechanisms may also be involved in general anesthesia. Propofol has been implicated in movement disorders. The cerebellum is important for motor coordination and motor learning. The aim of the present study was to investigate the propofol effect on excitatory synaptic transmissions in cerebellar cortex. METHODS: Excitatory postsynaptic currents by parallel fiber stimulation and complex spikes by climbing fiber stimulation were monitored in Purkinje cells of Wister rat cerebellar slice using whole-cell patch-clamp techniques. RESULTS: Decay time, rise time and amplitude of excitatory postsynaptic currents at parallel fiber Purkinje cell synapses and area of complex spikes at climbing fiber Purkinje cell synapses were significantly increased by propofol administration. CONCLUSION: The detected changes of glutamatergic synaptic transmission in cerebellar Purkinje cell, which determine cerebellar motor output, could explain cerebellar mechanism of motor deficits induced by propofol.


Subject(s)
Animals , Rats , Anesthesia, General , Anesthetics , Cerebellar Cortex , Cerebellum , Excitatory Postsynaptic Potentials , Learning , Movement Disorders , Patch-Clamp Techniques , Propofol , Purkinje Cells , Synapses , Synaptic Transmission
9.
Biosalud ; 15(2): 9-19, jul.-dic. 2016. ilus, tab
Article in Spanish | LILACS | ID: biblio-950975

ABSTRACT

Introducción: La calbindina (CB) es una proteína reguladora del calcio intracelular y la célula de Purkinje del cerebelo es la neurona con más alta concentración de CB. Se ha demostrado pérdida de inmunorreactividad a CB en diferentes áreas del sistema nervioso en ratones inoculados con virus de la rabia, pero faltaba estudiar este fenómeno en el cerebelo. Objetivo: Determinar el efecto de la inoculación con virus de la rabia sobre la expresión de CB en células de Purkinje del cerebelo de ratones. Metodología: Se inocularon ratones con el virus por vía intramuscular. Se sacrificaron los animales cuando alcanzaron la fase avanzada de la enfermedad y se fijaron mediante perfusión intracardiaca con paraformaldehído al 4%. Se les extrajo el cerebelo y se hicieron cortes sagitales de 50 micrómetros de espesor en un vibrátomo. Estos se procesaron mediante inmunohistoquímica para revelar la presencia de CB o de antígenos del virus de la rabia. El mismo procedimiento se realizó con animales no infectados (controles). Resultados: Las células de Purkinje fueron masivamente infectadas con el virus de la rabia. En las imágenes panorámicas observadas en el microscopio se comprobó que sólo estas células fueron inmunorreactivas a CB. No se hallaron diferencias significativas en la inmunorreactividad a CB, evaluada por densitometría óptica, entre los animales infectados y los controles. Conclusión: La expresión de CB en las células de Purkinje del cerebelo parece no afectarse por la infección con rabia, a diferencia de lo que se ha demostrado en otras áreas del sistema nervioso del ratón.


Introduction: Calbindin (CB) is a regulatory protein of intracellular calcium, and the cerebellar Purkinje cell is the neuron with the highest concentration of CB. Loss of CB immunoreactivity has been demonstrated in different areas of the nervous system in rabies virus-infected mice, but the study of this phenomena in the cerebellum lacked. Objective: To determine the effect of inoculation with rabies virus on the expression of CB in Purkinje cells of the cerebellum of mice. Methodology: Mice were intramuscularly inoculated with rabies virus. Animals were sacrificed when they reached an advanced stage of the disease and then they were fixed by intracardiac perfusion with 4% paraformaldehyde. Cerebellums were extracted and sagittal sections 50 microns thick were obtained in a vibratome. These were processed by immunohistochemistry to reveal the presence of CB protein or rabies virus antigens. The same procedure was performed with uninfected animals (controls). Results: Purkinje cells were massively infected with rabies virus. In the microscopic panoramic images observed was found that only these cells are immunoreactive to CB. No significant difference in CB immunoreactivity evaluated by optical densitometry was found between infected animals and controls. Conclusion: The expression of CB in Purkinje cells of the cerebellum appears not to be affected by infection with rabies unlike what has been shown in other areas of the mouse nervous system.

10.
Malaysian Journal of Health Sciences ; : 55-61, 2016.
Article in English | WPRIM | ID: wpr-626765

ABSTRACT

The emergence of research about the biological effects of electromagnetic field (EMF) have growing concern among researchers. The aim of this study was to investigate the effects on the brain of rats periodically exposed to 0.1 mT EMF. Total 24 adult male Sprague Dawley rats were subdivided randomly to 4 groups: 2 control groups (C1 6 hours: 6 h/ day for 5 days; C2 20 hours: 20 h/day for 5 days) and 2 treatment groups which exposed to 0.1 mT EMF (T1 6 hours: 6 h/day for 5 days; T2 20 hours: 20 h/day for 5 days). A significant decrease in the pyramidal cell number was higher as the exposure duration to EMF was extended (T1, p<0.05; T2, p<0.001). The total numbers of pyramidal cells for T1 was 15.18 % lower than of the total found in C1; and in concurring to the pattern, the number of pyramidal cells in T2 was 33.54 % lower than the total in C2. Similarly, there was a significant decrease of the Purkinje cell number as the duration exposure to EMF, extended (T1, p<0.05; T2, p<0.001). The total numbers of Purkinje cells for T1 was 11.20 % lower than C1, in T2 was 16.19 % lower than in C2. There were significant differences between the thickness of granular layer and molecular layer in the control groups and treatment groups. We also report a significant difference in the levels of norepinephrine in T2, 10.71 % higher than C2. Cumulatively, these results suggested that exposure to EMF can exert negative effect on rats brains.


Subject(s)
Electromagnetic Fields
11.
Article in English | IMSEAR | ID: sea-175148

ABSTRACT

Introduction: Datura stramonium (DS) is a tropical ubiquitous shrub which is often used to increase intoxication in some beverages and is also freely used as a hallucinogen. It is a depressant of the central nervous system, yet commonly smoked in like manner tobacco. The present study investigated changes induced by intoxication with DS on the purkinje cells and parallel fibres of the cerebellum in Wistar rats to further elucidate the effects of this drug on cerebellar structure. Materials and Methods: The study was conducted on both male and female Wistar rats (200-250 g). They were placed into three batches and four groups were derived from each batch, with eight animals per group. Ethanolic dried seed extract of DS was diluted in normal saline and administered intraperitoneally (I.P.) at a dose of 750mg/kg and given to the treatment groups: once in batch 1, twice in batch 2, twelve hourly and thrice in batch 3, eight hourly per day respectively for 4 weeks, while the control groups received an equivalent of normal saline. The rats were euthanized and sections of the cerebellum were histologically processed in all groups. Silver impregnation stain for degenerating axons and neurons was used to elucidate the actions of DS on purkinje cells and the parallel fibres of the cerebellum. Results: The result of IP administration of DS extract (750 mg/kg) given three times daily to the treated rats showed significant histological changes, which included atrophy of the parallel fibres but no significant changes in the purkinje cells of the cerebellum. Conclusions: Intoxication of DS seed as a result of excessive ingestion may have a selective degenerative effect on the parallel fibres of the granule cells of the cerebellum while the purkinje cells are spared; the implication being motor dysfunction.

12.
Article in English | IMSEAR | ID: sea-174862

ABSTRACT

Introduction: Lead, a heavy metal is well known for its toxic effects on the central nervous system. Clinically, overall effects of lead on different organ system are called plumbism. Diverse writing can be seen on the subject, but rarely there has been a comparison in any of these writings on different parts within the brain of the changes happening as the result of lead exposure. This study was taken up to draw a comparison and correlation of damaging effects on different parts of brain at microscopic level as a result of lead toxicity so that the affected elements in the tissue can be further connected to the histopathological and clinical outcomes of the lead toxicity. Materials and Methods: To conduct the study albino rats of Charles Foster strain were administered orally with 4% lead acetate in drinking water. The behavioral and clinical changes during the period of lead administration were closely observed that extended from irritability, agitation and aggressive behavior in the beginning to drastic fall in activity, indifference towards varieties of stimulus and severe motor deficit. At the end of an average of 17 days the rats were sacrificed for both gross and microscopic examination of brain for changes in the cerebral cortex, hippocampus, cerebellum, pons & medulla. The elements of the tissue observable as per the selected staining were the neurons, fibers, glia & the vessels. Results: The changes showed up with similarities between different parts as the shrinkage of neurons, damaged fibers, stunting of cell processes and increased glial cell population, whereas there were dissimilarities with regards to the extent of shrinkage of neuron and distribution of perineuronal spaces, vacuoles & the glial cells. Discussion and Conclusion: The comparative picture of the changes as a result of lead exposure showed widespread damage to nearly all the elements of the nervous tissue with reactive changes e.g. gliosis, and variations in the extend of changes in the selected brain parts. As a result these changes observed can be of used to correlate in the overall outcome of plumbism in relation to the functions of different parts of the brain.

13.
Brain & Neurorehabilitation ; : 90-95, 2015.
Article in English | WPRIM | ID: wpr-17768

ABSTRACT

Cerebellum serves an important function in diverse domain of motor, cognition control. Cerebellar non-invasive brain stimulation (NIBS) can provide a better comprehension of cerebellar circuity connecting to primary motor cortex. Cerebellar transcranial magnetic stimulation (TMS) activates Purkinje cells, causing increased inhibition of dentato-thalamo-cortical pathway. Assessing cerebellar-brain inhibition is useful for evaluating normal cerebellar functions and for understanding specific pathophysiology. Transcranial direct current stimulation (tDCS) has the polarity specific effect on cerebellar activity. Both TMS and tDCS can modulate cerebellar functions: motor learning, visuomotor adaptation, motor coordination, working memory and other cognitive domains. Further studies are encouraged to accumulate clinical and molecular evidences of neural plasticity induced by cerebellar NIBS. In the near future, cerebellar NIBS would play a crucial role in the field of neurorehabiliation.


Subject(s)
Brain , Cerebellum , Cognition , Comprehension , Learning , Memory, Short-Term , Motor Cortex , Neuronal Plasticity , Plastics , Purkinje Cells , Transcranial Magnetic Stimulation
14.
Chinese Journal of Pathophysiology ; (12): 664-668, 2015.
Article in Chinese | WPRIM | ID: wpr-461497

ABSTRACT

[ ABSTRACT] AIM:To investigate the effects of paeoniflorin ( Pae) on the functional responses induced by acute hypoxic insult in the rat cerebellar Purkinje cells ( PCs) .METHODS:The whole-cell patch clamp was used for the intra-cellular recording of PCs in the rat cerebellar slices to evaluate the changes of membrane potential, the excitability of PCs, and the parallel fibre ( PF)-PC excitatory postsynaptic currents ( EPSCs) upon acute hypoxic insult alone or with the pre-sence of Pae.RESULTS:PCs showed an initial hyperpolarization followed by brief depolarization and long lasting post-hy-poxia hyperpolarization after hypoxia exposure.Pae completely blocked hypoxia-induced hyperpolarization and decreased the amplitude and the duration of hypoxic depolarization.Hypoxia up-regulated the excitability of rat PCs.Pae didn’t show any significant effect on the hypoxia-induced hyperexcitability in PCs.Acute hypoxia induced long-term depression ( LTD) in rat cerebellar PF-PC EPSCs, and Pae partially reversed hypoxia-induced depression in PF-PC EPSCs.CONCLUSION:Pae significantly suppresses hypoxia-induced responses in rat PCs and probably increases the tolerance of rat PCs to acute hypoxia.

15.
J Biosci ; 2014 Jun; 39 (3): 401-413
Article in English | IMSEAR | ID: sea-161951

ABSTRACT

The speckle POZ protein, SPOP, is an adaptor of the Cul3-based ubiquitination process, and has been implicated in the carcinogenesis process. Despite recent elucidation of biological functions, regulation of SPOP gene expression has not been reported. In this study, the mRNA levels of the mouse SPOP (mSPOP) gene were first shown to vary noticeably in different tissues. However, the SPOP protein was detected in high abundance only in Purkinje cells of the cerebellum and seminiferous tubule of the testis, echoing previous reports of involvement of ubiquitination in neuron cells and in spermatogenesis. In other mouse tissues and human cancer cell lines analysed, only low SPOP protein levels were detected. The 3′-untranslated regions of both the mSPOP and human SPOP transcripts harbor a conserved putative miR-145 binding site (BS). In some tissues and cell lines, miR-145 and SPOP protein levels were in an inverse relationship suggesting miR-145 regulation. Luciferase assays of deletion and point mutation constructs of the miR-145 BS, and miR-145 induction by serum starvation that resulted in reduced endogenous SPOP levels provided further evidence that miR-145 is likely involved in post-transcriptional regulation of SPOP expression in selected tissues, and possibly with the participation of other miRNA species.

16.
J Biosci ; 2014 Jun; 39 (3): 401-413
Article in English | IMSEAR | ID: sea-161929

ABSTRACT

The speckle POZ protein, SPOP, is an adaptor of the Cul3-based ubiquitination process, and has been implicated in the carcinogenesis process. Despite recent elucidation of biological functions, regulation of SPOP gene expression has not been reported. In this study, the mRNA levels of the mouse SPOP (mSPOP) gene were first shown to vary noticeably in different tissues. However, the SPOP protein was detected in high abundance only in Purkinje cells of the cerebellum and seminiferous tubule of the testis, echoing previous reports of involvement of ubiquitination in neuron cells and in spermatogenesis. In other mouse tissues and human cancer cell lines analysed, only low SPOP protein levels were detected. The 3′-untranslated regions of both the mSPOP and human SPOP transcripts harbor a conserved putative miR-145 binding site (BS). In some tissues and cell lines, miR-145 and SPOP protein levels were in an inverse relationship suggesting miR-145 regulation. Luciferase assays of deletion and point mutation constructs of the miR-145 BS, and miR-145 induction by serum starvation that resulted in reduced endogenous SPOP levels provided further evidence that miR-145 is likely involved in post-transcriptional regulation of SPOP expression in selected tissues, and possibly with the participation of other miRNA species.

17.
Article in English | IMSEAR | ID: sea-151987

ABSTRACT

In the recent decade, there has been increasing concern on the hazard effect of drugs on different species. Stressful life events contribute to the development of many neurodegenerative and neuropsychiatric disorders including depression and anxiety. Alprazolam (ALP) is commonly used and approved for the medical treatment of panic and anxiety disorders, such as generalized anxiety or social anxiety disorders. Thus, it was of a particular interest to investigate the effect of ALP on the neurons of cerebellar cortex of mice, where mice have genomic similarities to human. So, biochemical, histological and ultrastructural investigations are reported on the cerebellum of adult male mice subjected to three different doses of ALP, for two months. These doses were equivalent to the human therapeutic doses as 0.5, 1 and 1.5 mg. In a dose dependant manner, significant decreases in the levels of both acetylcholine enzyme activities and total glutathione are recorded, indicating that the activity of acetylcholine esterase was inhibited by free radical formation. Little histopathological changes were observed in the cerebellar cortex of mice administered with 0.5 mg ALP. Marked alterations were observed in the Purkinje neurons of cerebellar cortex of mice administered with 1 and 1.5 mg ALP, where unstained haloes are seen around most of these cells. Their nuclei were eccentrically placed, and pyknotic. The intracellular structure of Purkinje cells showed dilatation of both rER and Golgi apparatus. Many small vesicles near the Golgi bodies were accumulated to form clusters, probably indicate disturbance in the vesicular transport between rER and Golgi apparatus. These results reflect the injured effect of high dose ALP on brain activity, performing in the possible ultrastructural abnormalities as well as its oxidative stress.

18.
Rio de Janeiro; s.n; 2013. 87 p. ilus.
Thesis in Portuguese | LILACS | ID: lil-711933

ABSTRACT

Lesões sistêmicas peri e pré-natais alteram o desenvolvimento do SNC, levando a problemas cognitivos e motores em crianças que podem perdurar por toda a vida. Um tipo particular de lesão é a hipóxia-isquemia (HI), caracterizada pela interrupção momentânea ou permanente do fluxo sanguíneo. Um dos mecanismos propostos para as lesões decorrentes da HI é a excitotoxicidade glutamatérgica. O uso de inibidores da neurotransmissão glutamatérgica tem sido estudados em diversos modelos de HI. Neste trabalho, avaliamos os efeitos morfofuncionais da administração de um antagonista não-competitivo do receptor de glutamato NMDA sobre o desenvolvimento do cerebelo. Ratas no 18º dia de gestação foram anestesiadas, os cornos uterinos expostos e as 4 artérias uterinas obstruídas por 45 minutos (Grupo H). Animais controle tiveram os úteros expostos, sem a obstrução (Grupo S). Após a cirurgia a gestação prosseguiu. Somente animais nascidos a termo foram utilizados. Um dia após o nascimento, metade de cada ninhada foi designada para receber MK801, 0,3mg/kg/dia, (grupos SM e HM) e a outra metade recebeu solução salina (grupos SS e HS), por 5 dias. Após anestesia e perfusão-fixação com paraformaldeído 4% aos 9, 23, 30 e 60 dias pós-natais, cortes parassagitais do cerebelo foram obtidos em criótomo e submetidos à imunohistoquímica para calbindina, GFAP, GLAST, PDGFRα e MBP. A partir de 45 dias de vida, os animais foram testados em vários de testes comportamentais: labirinto em cruz elevado (LCE), campo vazado (CV), ROTAROD, teste de caminhada sobre barras (ladder test) e teste do comprimento da passada (stride length). Aos 9 dias, a espessura da árvore dendrítica era menor nos animais SM, HS/HM, demonstrando efeitos deletérios tanto do MK801 quanto da HI. Menor número de células PDGFRα+ foi observado nos animais HS/HM, sem efeitos da administração de MK801. Aos 23 dias, maior número de células PDGFRα+ foi observado nos animais HM comparado aos outros 3 grupos, indicando efeito ...


Peri and prenatal systemic lesions alter CNS development leading to motor and cognitive problems in children that might persist throughout life. A particular kind of injury, the hypoxic ischemic (HI), is characterized by a permanent or temporary blockage of blood flow. One of the proposed mechanisms downstream from a HI event is called glutamatergic excitotoxicity. The administration of glutamate inhibitors has been studied in HI models for several years. In this work, we evaluated the effects of administration of a non-competitive antagonist of glutamate receptor, NMDA, on cerebellar development and behavioral tests of HI animals. Pregnant rats in the 18th gestational day were anesthetized, the uterine horns were exposed and the four uterine arteries were clamped for 45 minutes (group H). Sham controls had the uterine horns exposed, but no arteries were clamped (group S). Gestation proceeded after surgery. Only full term animals were used. One day after birth half the animals was assigned to receive either SALINE (groups SS and HS) or MK801 (groups SM and HM). Animals were anesthetized and perfused with 4% paraformaldehyde at 9, 23, 30 and 60 days of age. Parasagittal cerebellar sections were submitted to Calbindin, GFAP, GLAST, PDGFRα and MBP immunohistochemistry. Beginning at P45 animals were subjected to a battery of behavioral tests: elevated plus maze (EPM), hole board (HB), ROTAROD, ladder test and stride length. At P9 the dendritic tree of Purkinje cells were thinner in SM, HS/HM animals, indicating that both HI and MK801 are deleterious regarding this Purkinje cell differentiation. A lower number of PDGFRα+ cells was observed in HS/HM animals, with no effects of MK801 administration. At P23 a greater number of PDGFRα+ cells was found in HM animals when compared to the other 3 groups, demonstrating a neuroprotector effect of MK801. A lower number of myelinated fibers (MBP+) was observed in HS animals at P9, and MK801 administration reverse this ...


Subject(s)
Animals , Male , Female , Rats , Hypoxia-Ischemia, Brain/complications , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Excitatory Amino Acid Antagonists/administration & dosage , Myelin Sheath/metabolism , Purkinje Cells/metabolism , Cerebellum/growth & development , Cerebellum , Dizocilpine Maleate/administration & dosage , Oligodendroglia/metabolism , Amino Acid Transport System X-AG/metabolism
19.
Pesqui. vet. bras ; 32(11): 1107-1115, Nov. 2012. ilus, tab
Article in Portuguese | LILACS | ID: lil-658078

ABSTRACT

Algumas espécies de Solanum causam intoxicações em ruminantes caracterizadas clinicamente por desordens cerebelares e microscopicamente como doença do depósito lisossomal. Não há lesões de necropsia específicas e microscopicamente ocorrem vacuolização e perda de neurônios de Purkinje. Por ser Solanum paniculatum a espécie de ocorrência na região Nordeste, sendo responsável pelos surtos de intoxicação espontânea descrito no Estado de Pernambuco foi realizado um delineamento experimental para caracterizar o quadro clínico-patológico da intoxicação. Foram usados cinco bovinos, sendo quatro no grupo experimental (GE) e um animal no controle (GC), de seis meses de idade, sem raça definida, com peso de 120 Kg, mantidos em baias durante cinco meses na Clínica de Bovinos de Garanhuns/UFRPE. Os animais receberam a planta, colhida nas propriedades em que ocorreram os surtos naturais, na dosagem de 5g/kg/PV/dia da planta dessecada misturada na ração por ingestão natural. Semanalmente realizou-se o Head Raising Test para determinar os sinais cerebelares e quando positivo os animais foram submetidos à colheita de sangue e do líquido céfalo-raquidiano e em seguida foi feito à eutanásia.


O SNC e a rete mirabile foram fixados em formol a 10% tamponado, processados rotineiramente e corados pela hematoxilina e eosina para avaliação histopatológica. Foi realizada análise morfométrica das lesões cerebelares. Para avaliação dos resultados laboratoriais utilizou-se análise descritiva e em relação à morfometria, empregou-se o teste T de Student (p<0.05) na contagem de células de Purkinje e para a espessura da camada molecular do cerebelo o teste de Mann Whitney, com nível de 5% de significância. Três animais apresentaram sinais de intoxicação com tempo em média de 90 dias e um com 155 dias. Os sinais clínicos observados foram ataques convulsivos transitórios, e distúrbios do equilíbrio. Na necropsia não foram encontradas lesões específicas da intoxicação. Não houve alterações no hemograma e no líquido céfalo-raquidiano causado pela planta. No histopatológico havia principalmente vacuolização fina do pericário e perda de células de Purkinje, com degeneração Walleriana e esferóides axonais na camada granular e na substância branca medular, com proliferação dos astrócitos de Bergman. Vacuolização e necrose neuronal também foram observadas no óbex, pedúnculos cerebelares e colículos rostral e caudal e raramente no tálamo, núcleos da base, hipocampo e medula oblonga. Na análise morfométrica não houve diferença significativa (p<0,05) entre o número de células de Purkinje e a espessura da camada molecular entre o GE e GC, demonstrando que apesar dos bovinos desenvolverem quadro clínico da intoxicação e alterações histopatológicas acentuadas, mas nestas condições experimentais não ocorreram alteração morfométricas significativas em relação ao GC.


Sugerindo que há necessidade de um tempo de administração maior da planta para o aparecimento de lesões mais acentuadas como as que ocorrem em casos naturais. Os resultados laboratoriais de sangue e do líquido céfalo-raquidiano não refletem alterações relacionadas à intoxicação pela planta.


Some species of Solanum cause poisoning in ruminants clinically characterized by cerebellar disorders and microscopically lysosomal storage disease. There are no specific necropsy injuries and microscopically occurs vacuolation and Purkinje cells loss. Since Solanum paniculatum is the species of greater occurrence in the Northeast region of Brazil and is responsible for spontaneous intoxication outbreaks in Pernambuco State, an experimental delineation was carried out to characterize the clinical and pathological condition of the intoxication. Five cattle were randomly allotted in two groups, with four animals in the experimental group (EG) and one animal as control (CG), with six months of age, no defined breed and weighting 120 kg. All animals were kept in stalls along 5 months in the Clínica de Bovinos de Garanhuns/UFRPE. All animals from the experimental group were fed 5g/kg/body weight/day of the dried leaves of S. paniculatum which was mixed in the ration. The plant was collected in farms where outbreaks of intoxication were described. A Head Raising Test was weekly performed to determine the occurrence of any cerebellum clinical signs and when the result was positive the animal was submitted to a blood and cerebrospinal fluid sampling and subsequently euthanized.


Subject(s)
Animals , Cattle , Autopsy , Purkinje Cells , Gaucher Disease/veterinary , Central Nervous System , Solanum/poisoning , Nerve Degeneration/veterinary , Toxicological Symptoms
20.
Anatomy & Cell Biology ; : 121-127, 2012.
Article in English | WPRIM | ID: wpr-14604

ABSTRACT

The toxic effects of morphine sulfate in the adult cerebral cortex and one-day neonatal cerebellum have been studied. This study was carried out to evaluate the effect of maternal morphine exposure during gestational and lactation period on the Purkinje cells and cerebellar cortical layer in 18- and 32-day-old mice offspring. Thirty female mice were randomly allocated into cases and controls. In cases, animals received morphine sulfate (10 mg/kg/body weight intraperitoneally) during the 7 days before mating, gestational day (GD 0-21) 18 or 32. The controls received an equivalent volume of saline. The cerebellum of six infants for each group was removed and each was stained with cresyl violet. Quantitative computer-assisted morphometric study was done on cerebellar cortex. The linear Purkinje cell density in both experimental groups (postnatal day [P]18, 23.40+/-0.5; P32, 23.45+/-1.4) were significantly reduced in comparison with the control groups (P18, 28.70+/-0.9; P32, 28.95+/-0.4) (P<0.05). Purkinje cell area, perimeter and diameter at apex and depth of simple lobules in the experimental groups were significantly reduced compared to the controls (P<0.05). The thickness of the Purkinje layer of the cerebellar cortex was significantly reduced in morphine treated groups (P<0.05). This study reveals that morphine administration before pregnancy, during pregnancy and during the lactation period causes Purkinje cells loss and Purkinje cell size reduction in 18- and 32-day-old infant mice.


Subject(s)
Adult , Animals , Female , Humans , Infant , Mice , Pregnancy , Benzoxazines , Cell Count , Cell Size , Cerebellar Cortex , Cerebellum , Cerebral Cortex , Lactation , Morphine , Purkinje Cells , Viola
SELECTION OF CITATIONS
SEARCH DETAIL