Papers by Abdeljalil Elgot
Neuroscience Letters, Aug 1, 2014
c Centre national d'études et de recherches sur le Sahara (CNERS), Morocco h i g h l i g h t s • ... more c Centre national d'études et de recherches sur le Sahara (CNERS), Morocco h i g h l i g h t s • Aluminum induced neurological effects in humans and animals. • Al in drinking water is a risk factor in Alzheimer's disease. • We study the effect of chronic intoxication with Al on 5HT system and glycoprotein secretion. • Al alters the serotonin system in the DRN and secretory activity in the SCO.
Acta histochemica, Oct 1, 2012
Dehydration is a powerful stimulus causing disequilibrium in homeostasis of water and electrolyte... more Dehydration is a powerful stimulus causing disequilibrium in homeostasis of water and electrolytes resulting from depletion in total body water. Most studies have focused on domestic and laboratory animals; however, the study of desert animals allows improved understanding about water balance and resistance to dehydration and associated behavioral changes, including those related to mood disorders. Meriones shawi (Shaw's Jird) is a desert rodent characterized by its resistance to long periods of thirst that can extend for several months. In the present study, M. shawi were subjected to water deprivation for 1 and 3 months. We used 5-HT immunohistochemistry to evaluate the effects of prolonged dehydration on the serotoninergic system in both dorsal and median raphe nuclei (DRN, MRN), which are the main sources of 5-HT input to several brain areas. In addition, a dark/light box was used to evaluate the anxiolytic-like or anxiogenic-like effects of dehydration on M. shawi. The results showed a reduction in the 5-HT immunolabelling in both DRN and MRN following 1 and 3 months of dehydration. This diminution of serotonin immunoreactivity was accompanied by noticeable changes in anxiety behavior of Meriones, with animals spending more time in the light box, suggesting anxiogenic-like effects caused by dehydration. Overall, the results indicate that dehydration is able to reduce serotoninergic neurotransmission, which might be involved in generating anxiety behavior in this desert animal.
Comptes Rendus Biologies, Jul 1, 2012
Alteration of dopaminergic innervation and voluntary movements after long period of thirst in a s... more Alteration of dopaminergic innervation and voluntary movements after long period of thirst in a semi-desert rodent, Meriones shawi: Behavioral and immunohistochemical studies Alte´ration de l'innervation dopaminergique et les mouvements volontaires apre`s une longue pe´riode de soif chez un rongeur semi-de´sertique, Meriones shawi : e´tude comportementale et immunohistochimique
Journal of Chemical Neuroanatomy, Dec 1, 2019
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Journal of Chemical Neuroanatomy, Mar 1, 2021
Aluminum (Al) is recognized potent neurotoxic metal, which causes oxidative stress leading to int... more Aluminum (Al) is recognized potent neurotoxic metal, which causes oxidative stress leading to intracellular accumulation of reactive oxygen species (ROS) and neuronal cell death in various neurodegenerative diseases. Among several medicinal plants with beneficial effects on health, curcumin acts as a multi-functional drug with antioxidant activity. Thus, the purpose of the present study was to evaluate the protective effect of curcumin against aluminum induced-oxidative stress and astrocytes death, in vitro ad in vivo. Incubation of cultured rat astrocytes with two concentrations of Al (37 µM and 150 µM) for 1 h provoked a dose-dependent reduction of the number of living cells as evaluated by Fluorescein diacetate and lactate dehydrogenase assay. Al-treated cells exhibited a reduction of both superoxide dismutase (SOD) and catalase activities. Pretreatment of astrocytes with curcumin (81 µM) prevented Al-induced cell death. Regarding in vivo study, rats were exposed acutely during three consecutive days to three different doses of Al (25 mg/kg, 50 mg/kg and 100 mg/kg, i.p injection), together with curcumin treatment (30 mg/kg). For the chronic model, animals were exposed to Al (3 g/l) in drinking water from intrauterine age to 4 months ages, plus curcumin treatment (175 mg/kg). Data showed that both acute and chronic Al intoxication induced an obvious astrogliosis within motor cortex and hippocampus, while, such effects were restored by curcumin. We showed herein that Al was highly toxic, induced astrocytes death. Then, curcumin protected astrocytes against Al-toxicity. The cytoprotective potential of curcumin is initiated by stimulation of endogenous antioxidant system.
Acta histochemica, Feb 1, 2018
Meriones shawi (M. shawi) is a particular semi-desert rodent known by its resistance to long peri... more Meriones shawi (M. shawi) is a particular semi-desert rodent known by its resistance to long periods of thirst. The aim of the present investigation is to clarify the underlying mechanisms allowing M. shawi to resist to hard conditions of dehydration. For this reason we used two different approaches: i) a morphometric study, which consists in measuring the effect of dehydration on body and kidneys weights as well as the report kidney weight/ body weight, ii) By immunohistochemistry, we proceed to study the effect of dehydration on the immunoreactivity of central vasopressin (AVP) and the kidney aquaporin-2 (AQP-2) which is a channel protein that allows water to permeate across cell membranes. Our results showed both a body mass decrease accompanied by a remarkable kidneys hypertrophy. The immunohistochemical study showed a significant increase of AQP-2 immunoreactivity in the medullar part of Meriones kidneys allowing probably to Meriones a great ability to water retention. Consistently, we demonstrate that the increased AQP-2 expression occurred together with an increase in vasopressin (AVP) expression in both hypothalamic supraoptic (SON) and paraventricular nucleus (PVN), which are a major hub in the osmotic control circuitry. These various changes seen either in body weight and kidneys or at the cellular level might be the basis of peripheral control of body water homeostasis, providing to M. shawia strong resistance against chronic dehydration.
Neuroscience Letters, Apr 1, 2012
Various lines of evidence indicate that astrocytes can undergo morphological changes that modify ... more Various lines of evidence indicate that astrocytes can undergo morphological changes that modify their relationship to adjacent neurons in response to physiological stimulation such as dehydration. Supraoptic (SON) and paraventricular (PVN) nuclei of hypothalamus represent obvious examples of activity-dependent neuro-astrocytic plasticity. In the present study, Meriones shawi is used as an animal model. Moreover, GFAP and vasopressin expressions are used as indicators successively of astrocytes and neuronal activations. In order to evaluate the reversibility of the neuro-astrocytic plasticity in SON and PVN, prolonged episode of water deprivation followed by episode of rehydration were examined. Hence, we studied the immunoreactivity in various hydration states: water ad libitum, dehydration, and rehydration of animals. Our results showed that dehydration of Meriones induced a significant decrease of GFAP immunoreactivity accompanied by a significant increase of AVP immunoreactivity, the latter concerns both cell bodies and fibers in the same hypothalamic nuclei SON and PVN. Conversely, rehydration of animals shows a reversible phenomenon leading a return of vasopressin and GFAP immunoreactivities to the control level. These results show that both astrocytes and vasopressin neurons display a remarkable structural and physiological plasticity, allowing to M. shawi, a great ability to support the hostile conditions in dry environment.
Brain Research, Feb 1, 2011
Supraoptic (SON) and paraventricular (PVN) nuclei are part of the hypothalamicneurohypophysial sy... more Supraoptic (SON) and paraventricular (PVN) nuclei are part of the hypothalamicneurohypophysial system, they constitute the main source for vasopressin and they represent also obvious examples of activity-dependent neuroglial plasticity. Certain physiological conditions such as dehydration are accompanied by a structural remodeling of the neurons, their synaptic inputs and their surrounding glia. In the present work, an adult Meriones shawi (a rodent adapted to desert life) is used as an animal model. Using GFAP and vasopressin expressions as indicators successively of astrocytes and neuronal activations, the effect of a prolonged episode of water deprivation on the SON and PVN, hypothalamus nuclei were examined. We studied the immunoreactivity of GFAP and vasopressin in various hydration states (total deprivation of drinking water for 1 and 2 months compared to hydrated animals). Prolonged dehydration produces an important decrease of GFAP immunoreactivity in both SON and PVN after 1 and 2 months of water restriction. This decrease is accompanied by increased vasopressin immunoreactivity following the same periods of water deprivation. These findings may explain a real communication between vasopressin neurons and their surrounding astrocytes, thus the retraction of astrocytes and their processes is accompanied by an enhancement of vasopressin neuron density and their projecting fibers in response to this osmotic stress situation. Furthermore, these data could open further investigations concerning the possible involvement of the communication between astrocytes and vasopressin neurons in both PVN and SON in the regulation of Meriones hydrous balance and resistance to dehydration.
Parkinsonism & Related Disorders, 2016
Objectives: Parkinson's disease (PD) is a chronic neurodegenerative disorder with boosted rate in... more Objectives: Parkinson's disease (PD) is a chronic neurodegenerative disorder with boosted rate in the aging population. The classic motor symptoms of PD result from progressive dopaminergic neurons death within substantia nigra. Some finding support the involvement of heavy metals, as an exogenous risk factor such as copper (Cu), able to trigger neurotransmitter imbalances including dopamine (DA), those dysfunctions were involved in the neuropathology of PD. We aimed to describe the effect of acute and chronic Cu intoxication on dopaminergic system in rat. Methods: Adult male rats were injected intraperitoneally with 10mg/Kg for three consecutive days in acute model; in chronic model, rats were intoxicated with 0.125% of Cu in drinking water from gestation to adulthood. Locomotor behavior was assessed using the open field test and rats were scarified for an immunohistochemical analysis of tyrosine hydroxylase, in Substantia Nigra compacta (SNc), in the ventral tegmental area (VTA) and in the subsequent striatal outputs Results: we reported, in acute Cu intoxicated rats, a loss of TH expression within SNc, VTA and the subsequent striatal outputs, those alterations were correlated to behavioral abnormalities such as a severe loss of locomotor performance in the two animal models. Conclusions: Such finding reinforces the possible involvement of Cu, as risk factor for PD and may allow us to deeply understand the pathophysiology of the neurodegenerative diseases in their environmental component.
Comptes Rendus Biologies, Apr 1, 2012
Aziz Chokri1, Younes Brouki2, Aziz Eloırdi2, Mohamed Barkaoui2, Abdeljalil Elgot3, Mounir Ouzir4,... more Aziz Chokri1, Younes Brouki2, Aziz Eloırdi2, Mohamed Barkaoui2, Abdeljalil Elgot3, Mounir Ouzir4, 5 1 Security Dynamics Research Laboratory, Institute of Sport Sciences, University Hassan First, Settat 2 Institute of Sport Sciences, University Hassan First, Settat 3 Laboratory of Sciences and Health Technologies, High Institute of Health Sciences, University Hassan First, Settat 4 Department of Biology, Group of Research in Physiology and Physiopathology, Faculty of Sciences, Mohammed V University, Rabat 5 Higher Institute of Nursing Professions and Health Techniques (ISPITS Beni Mellal), Beni Mellal, Morocco Burnout among healthcare professionals in Morocco Burnout among healthcare professionals in Morocco: impact of physical activity and work-related factors during COVID-19
Journal of Chemical Neuroanatomy, 2021
Aluminum (Al) is recognized potent neurotoxic metal, which causes oxidative stress leading to int... more Aluminum (Al) is recognized potent neurotoxic metal, which causes oxidative stress leading to intracellular accumulation of reactive oxygen species (ROS) and neuronal cell death in various neurodegenerative diseases. Among several medicinal plants with beneficial effects on health, curcumin acts as a multi-functional drug with antioxidant activity. Thus, the purpose of the present study was to evaluate the protective effect of curcumin against aluminum induced-oxidative stress and astrocytes death, in vitro ad in vivo. Incubation of cultured rat astrocytes with two concentrations of Al (37 µM and 150 µM) for 1 h provoked a dose-dependent reduction of the number of living cells as evaluated by Fluorescein diacetate and lactate dehydrogenase assay. Al-treated cells exhibited a reduction of both superoxide dismutase (SOD) and catalase activities. Pretreatment of astrocytes with curcumin (81 µM) prevented Al-induced cell death. Regarding in vivo study, rats were exposed acutely during three consecutive days to three different doses of Al (25 mg/kg, 50 mg/kg and 100 mg/kg, i.p injection), together with curcumin treatment (30 mg/kg). For the chronic model, animals were exposed to Al (3 g/l) in drinking water from intrauterine age to 4 months ages, plus curcumin treatment (175 mg/kg). Data showed that both acute and chronic Al intoxication induced an obvious astrogliosis within motor cortex and hippocampus, while, such effects were restored by curcumin. We showed herein that Al was highly toxic, induced astrocytes death. Then, curcumin protected astrocytes against Al-toxicity. The cytoprotective potential of curcumin is initiated by stimulation of endogenous antioxidant system.
Acta Histochemica, 2018
Meriones shawi (M. shawi) is a particular semi-desert rodent known by its resistance to long peri... more Meriones shawi (M. shawi) is a particular semi-desert rodent known by its resistance to long periods of thirst. The aim of the present investigation is to clarify the underlying mechanisms allowing M. shawi to resist to hard conditions of dehydration. For this reason we used two different approaches: i) a morphometric study, which consists in measuring the effect of dehydration on body and kidneys weights as well as the report kidney weight/ body weight, ii) By immunohistochemistry, we proceed to study the effect of dehydration on the immunoreactivity of central vasopressin (AVP) and the kidney aquaporin-2 (AQP-2) which is a channel protein that allows water to permeate across cell membranes. Our results showed both a body mass decrease accompanied by a remarkable kidneys hypertrophy. The immunohistochemical study showed a significant increase of AQP-2 immunoreactivity in the medullar part of Meriones kidneys allowing probably to Meriones a great ability to water retention. Consistently, we demonstrate that the increased AQP-2 expression occurred together with an increase in vasopressin (AVP) expression in both hypothalamic supraoptic (SON) and paraventricular nucleus (PVN), which are a major hub in the osmotic control circuitry. These various changes seen either in body weight and kidneys or at the cellular level might be the basis of peripheral control of body water homeostasis, providing to M. shawia strong resistance against chronic dehydration.
Journal of Chemical Neuroanatomy, 2019
Aluminum (Al) among the abundant metals on the earth crust, is able to cross the biological barri... more Aluminum (Al) among the abundant metals on the earth crust, is able to cross the biological barriers via the gastrointestinal and lung tissues. Once in the body, this heavy metal accumulates in different organs, especially the central nervous system. Though its influence is evidently shown in the substantia nigra of Parkinson's disease patients and other brain areas in other neurodegenerative diseases, few studies have demonstrated that Al could trigger profound changes in neurotransmission systems including the dopaminergic (DAergic) system. A variety of medicinal plants may be prescribed in such contamination, including some culinary spices such as Curcumin (Cur). Several studies have proven Cur to exhibit a wide variety of biological and pharmacological activities, especially its antioxidant potential. Using the immunohistochemistry, of tyrosine hydroxylase (TH), in the midbrain substantia nigra pars compact (SNc) and the ventral tegmental area (VTA) and the open field test, we examined the DAergic system together with the locomotor behavior respectively in rats exposed chronically to Al (0,3%) in drinking water during 4 months since the intra-uterine age, as well as the neuroprotective effect of the concomitant administration of Cur I (30 mg/kg B.W) of chronic Al exposed rats. Our results have shown a significant decrease of TH immureactivity in both SNc and VTA associated to a loss of the number of crossed boxes, leading to a difficient locomotor performance in the Al group while Cur I prevents such TH immunoreactivity impairment and maintains a higher locomotor activity in the Al-CurI group. Our findings lead to suppose a powerful and obvious neuroprotective potential of CurI against Al-induced neurotoxicity of the DAergic system involved in the control of the locomotor behavior.
Parkinsonism & Related Disorders, 2016
Objectives: Parkinson's disease (PD) is a chronic neurodegenerative disorder with boosted rate in... more Objectives: Parkinson's disease (PD) is a chronic neurodegenerative disorder with boosted rate in the aging population. The classic motor symptoms of PD result from progressive dopaminergic neurons death within substantia nigra. Some finding support the involvement of heavy metals, as an exogenous risk factor such as copper (Cu), able to trigger neurotransmitter imbalances including dopamine (DA), those dysfunctions were involved in the neuropathology of PD. We aimed to describe the effect of acute and chronic Cu intoxication on dopaminergic system in rat. Methods: Adult male rats were injected intraperitoneally with 10mg/Kg for three consecutive days in acute model; in chronic model, rats were intoxicated with 0.125% of Cu in drinking water from gestation to adulthood. Locomotor behavior was assessed using the open field test and rats were scarified for an immunohistochemical analysis of tyrosine hydroxylase, in Substantia Nigra compacta (SNc), in the ventral tegmental area (VTA) and in the subsequent striatal outputs Results: we reported, in acute Cu intoxicated rats, a loss of TH expression within SNc, VTA and the subsequent striatal outputs, those alterations were correlated to behavioral abnormalities such as a severe loss of locomotor performance in the two animal models. Conclusions: Such finding reinforces the possible involvement of Cu, as risk factor for PD and may allow us to deeply understand the pathophysiology of the neurodegenerative diseases in their environmental component.
Acta Histochemica, 2016
Hepatic encephalopathy (HE) is a neuropsychiatric disorder that occurs in both acute and chronic ... more Hepatic encephalopathy (HE) is a neuropsychiatric disorder that occurs in both acute and chronic liver failure. However, the pathomechanisms of the disease remains obscure. Neuropathological studies have demonstrated a primary gliopathy in humans as well as in animal models of chronic and acute liver failure. Here, we have investigated in an animal model of mild HE: the bile duct ligated rat (BDL) at the cirrhotic stage (4 weeks after surgery), the expression of the key marker of mature astrocytes; the glial fibrillary acidic protein (GFAP) in different brain areas such as: Substantia nigra pars compacta (SNc), Ventral tegmental area (VTA), hippocampus, dorsal striatum and brain cortex by means of immunohistochemistry. The immunohistochemical study showed, in BDL compared to the operated controls (shams), a diminished astrocyte reactivity corresponding to a loss of GFAP expression within SNc, VTA, hippocampus and dorsal striatum (p < 0.05),whereas in the brain cortex astrocytes appeared strongly immunoreactive with increased GFAP expression (p < 0.05) as compared to shams. Our finding demonstrated differential astroglial responses which depend to the specificity of the area investigated and its particular neuronal neighboring environment, and could have possible outcomes on the diverse neuronal functions especially those observed during the different episodes of hepatic encephalopathy.
International journal of developmental neuroscience : the official journal of the International Society for Developmental Neuroscience, Jan 27, 2015
Prenatal exposure to valproic acid (VPA) in rat offspring is capable of inducing experimental aut... more Prenatal exposure to valproic acid (VPA) in rat offspring is capable of inducing experimental autism with neurobehavioral aberrations. This study investigated the effect of docosahexaenoic acid (DHA) on hippocampal cell death, learning and memory alteration in an experimental rat autism model. We found that DHA supplementation (75, 150 or 300mg/kg/day, 21 days) rescued the VPA (600mg/kg) induced DHA reduction in plasma and hippocampus in a dose-dependent manner, increased the levels of hippocampal p-CaMKII and p-CREB without affecting total protein level, and altered BDNF-AKT-Bcl-2 signaling pathway, as well as inhibited the activity of caspase-3. DHA also influenced the content of malondialdehyde (MDA) and the activities of antioxidant enzymes in the VPA-treated offspring. Consistent with the previous results, we also observed that 300mg/kg DHA supplementation markedly increased the cell survival, decreased the cell apoptosis, and increased mature neuronal cell in the hippocampus i...
Neuroscience letters, Jan 8, 2014
Aluminum (Al) causes multiple impairments in several body systems including the central nervous s... more Aluminum (Al) causes multiple impairments in several body systems including the central nervous system. In fact, Al exposure has been mostly associated with neurological dysfunctions that occur in some brain diseases. The effect of Al neurotoxicity on the dopaminergic system is well documented, but this effect on the serotoninergic system is poorly studied. The aim of this work is to evaluate the effect of chronic Al intoxication (0.3% of aluminum chloride exposure from the intra-uterine age until 4 months of adult age) on dorsal raphe nucleus (DRN) which is the main source of serotonin, and also on the glycoprotein secretion of subcomissural organ (SCO), receiving important serotoninergic innervation. This will be executed using immunohistochemistry procedure, with both the anti serotonin and the anti Reissner's fiber antibodies in the rat. Our results showed a significant increase of serotonin immunoreactivity in the DRN, accompanied by a noticeable decrease of RF immunoreacti...
Neuroscience Letters, 2009
Water deprivation is a stress that has been associated with activation of several endocrine syste... more Water deprivation is a stress that has been associated with activation of several endocrine systems, including circumventricular organs of the central nervous system. The sub-comissural organ (SCO), characterized by its glycoprotein secretion called Reissner&amp;amp;amp;amp;#39;s fiber has been suggested to play a role in the regulation of body water balance. Meriones shawi, a semi-desertic rodent characterized by its resistance to long periods of thirst was subjected to water deprivation for 1 and 3 months. Effect of water deprivation was evaluated immunohistochemically on 5-hydroxytryptamine (5-HT; serotonin) system and glycoprotein secretion of the SCO. Our findings demonstrate significant reduction of anti-Reissner&amp;amp;amp;amp;#39;s fiber immunoreactive materials within basal and apical parts of the SCO ependymocytes. These changes seem to be the consequence of reduced control by 5-HT fibers reaching the SCO as a concomitant and significant reduction of anti-5-HT immunoreactive fibers are also observed following water deprivation. 5-HT immunoreactive reduction is seen in several regions in the brain including the neurons of origin within the dorsal raphe nucleus and the projecting supra and sub-ependymal fibers reaching the classical ependyma of the third ventricle. The extent of Reissner&amp;amp;amp;amp;#39;s fiber and 5-HT immunoreactive changes significantly correlates with the severity of water restriction. We suggest that water deprivation causes changes of the classical ependyma and the specialized ependyma that differentiates into the SCO as well as other cirumventricular organs such as the subfornical organ and the organum vasculosum laminae terminalis known to control drinking behaviors.
Neuroscience Letters, 2012
Various lines of evidence indicate that astrocytes can undergo morphological changes that modify ... more Various lines of evidence indicate that astrocytes can undergo morphological changes that modify their relationship to adjacent neurons in response to physiological stimulation such as dehydration. Supraoptic (SON) and paraventricular (PVN) nuclei of hypothalamus represent obvious examples of activity-dependent neuro-astrocytic plasticity. In the present study, Meriones shawi is used as an animal model. Moreover, GFAP and vasopressin expressions are used as indicators successively of astrocytes and neuronal activations. In order to evaluate the reversibility of the neuro-astrocytic plasticity in SON and PVN, prolonged episode of water deprivation followed by episode of rehydration were examined. Hence, we studied the immunoreactivity in various hydration states: water ad libitum, dehydration, and rehydration of animals. Our results showed that dehydration of Meriones induced a significant decrease of GFAP immunoreactivity accompanied by a significant increase of AVP immunoreactivity, the latter concerns both cell bodies and fibers in the same hypothalamic nuclei SON and PVN. Conversely, rehydration of animals shows a reversible phenomenon leading a return of vasopressin and GFAP immunoreactivities to the control level. These results show that both astrocytes and vasopressin neurons display a remarkable structural and physiological plasticity, allowing to M. shawi, a great ability to support the hostile conditions in dry environment.
Uploads
Papers by Abdeljalil Elgot