Résumé
<p><b>Background</b>Glehnia littoralis has been used for traditional Asian medicine, which has diverse therapeutic activities. However, studies regarding neurogenic effects of G. littoralis have not yet been considered. Therefore, in this study, we examined effects of G. littoralis extract on cell proliferation, neuroblast differentiation, and the maturation of newborn neurons in the hippocampus of adult mice.</p><p><b>Methods</b>A total of 39 male ICR mice (12 weeks old) were randomly assigned to vehicle-treated and 100 and 200 mg/kg G. littoralis extract-treated groups (n = 13 in each group). Vehicle and G. littoralis extract were orally administrated for 28 days. To examine neurogenic effects of G. littoralis extract, we performed immunohistochemistry for 5-bromo-2-deoxyuridine (BrdU, an indicator for cell proliferation) and doublecortin (DCX, an immature neuronal marker) and double immunofluorescence staining for BrdU and neuronal nuclear antigen (NeuN, a mature neuronal marker). In addition, we examined expressional changes of brain-derived neurotrophic factor (BDNF) and its major receptor tropomyosin-related kinase B (TrkB) using Western blotting analysis.</p><p><b>Results</b>Treatment with 200 mg/kg, not 100 mg/kg, significantly increased number of BrdU-immunoreactive () and DCX cells (48.0 ± 3.1 and 72.0 ± 3.8 cells/section, respectively) in the subgranular zone (SGZ) of the dentate gyrus (DG) and BrdU/NeuN cells (17.0 ± 1.5 cells/section) in the granule cell layer as well as in the SGZ. In addition, protein levels of BDNF and TrkB (about 232% and 244% of the vehicle-treated group, respectively) were significantly increased in the DG of the mice treated with 200 mg/kg of G. littoralis extract.</p><p><b>Conclusion</b>G. littoralis extract promots cell proliferation, neuroblast differentiation, and neuronal maturation in the hippocampal DG, and neurogenic effects might be closely related to increases of BDNF and TrkB proteins by G. littoralis extract treatment.</p>
Sujets)
Animaux , Mâle , Souris , Apiaceae , Chimie , Technique de Western , Facteur neurotrophique dérivé du cerveau , Métabolisme , Différenciation cellulaire , Prolifération cellulaire , Gyrus denté , Biologie cellulaire , Hippocampe , Biologie cellulaire , Immunohistochimie , Protéines associées aux microtubules , Métabolisme , Neurogenèse , Neuropeptides , Métabolisme , Extraits de plantes , Pharmacologie , Récepteur trkB , MétabolismeRésumé
Cardiac arrest (CA) is sudden loss of heart function and abrupt stop in effective blood flow to the body. The patients who initially achieve return of spontaneous circulation (RoSC) after CA have low survival rate. It has been known that multiorgan dysfunctions after RoSC are associated with high morbidity and mortality. Most previous studies have focused on the heart and brain in RoSC after CA. Therefore, the aim of this research was to perform serological, physiological, and histopathology study in the lung and to determine whether or how pulmonary dysfunction is associated with low survival rate after CA. Experimental animals were divided into sham-operated group (n=14 at each point in time), which was not subjected to CA operation, and CA-operated group (n=14 at each point in time), which was subjected to CA. The rats in each group were sacrificed at 6 hours, 12 hours, 24 hours, and 2 days, respectively, after RoSC. Then, pathological changes of the lungs were analyzed by hematoxylin and eosin staining, Western blot and immunohistochemistry for tumor necrosis factor α (TNF-α). The survival rate after CA was decreased with time past. We found that histopathological score and TNF-α immunoreactivity were significantly increased in the lung after CA. These results indicate that inflammation triggered by ischemia-reperfusion damage after CA leads to pulmonary injury/dysfunctions and contributes to low survival rate. In addition, the finding of increase in TNF-α via inflammation in the lung after CA would be able to utilize therapeutic or diagnostic measures in the future.
Sujets)
Animaux , Humains , Rats , Technique de Western , Encéphale , Éosine jaunâtre , Coeur , Arrêt cardiaque , Hématoxyline , Immunohistochimie , Inflammation , Poumon , Modèles animaux , Mortalité , Taux de survie , Facteur de nécrose tumorale alphaRésumé
The genus Populus (poplar) belonging to the Salicaceae family has been used in traditional medicine, and its several species show various pharmacological properties including antioxidant and anti-inflammatory effects. No study regarding protective effects of Populus species against cerebral ischemia has been reported. Therefore, in the present study, we examined neuroprotective effects of ethanol extract from Populus tomentiglandulosa (Korea poplar) in the hippocampal cornu ammonis (CA1) area of gerbils subjected to 5 minutes of transient global cerebral ischemia. Pretreatment with 200 mg/kg of P. tomentiglandulosa extract effectively protected CA1 pyramidal neurons from transient global cerebral ischemia. In addition, glial fibrillary acidic protein immunoreactive astrocytes and ionized calcium binding adapter molecule 1 immunoreactive microglia were significantly diminished in the ischemic CA1 area by pretreatment with 200 mg/kg of P. tomentiglandulosa extract. Briefly, our results indicate that pretreatment with P. tomentiglandulosa extract protects neurons from transient cerebral ischemic injury and diminish cerebral ischemia-induced reactive gliosis in ischemic CA1 area. Based on these results, we suggest that P. tomentiglandulosa can be used as a potential candidate for prevention of ischemic injury.
Sujets)
Humains , Astrocytes , Encéphalopathie ischémique , Calcium , Éthanol , Gerbillinae , Protéine gliofibrillaire acide , Gliose , Hippocampe , Médecine traditionnelle , Microglie , Neurones , Neuroprotecteurs , Populus , Cellules pyramidales , SalicaceaeRésumé
<p><b>BACKGROUND</b>Glehnia littoralis, as a traditional herbal medicine to heal various health ailments in East Asia, displays various therapeutic properties including antioxidant effects. However, neuroprotective effects of G. littoralis against cerebral ischemic insults have not yet been addressed. Therefore, in this study, we first examined its neuroprotective effects in the hippocampus using a gerbil model of transient global cerebral ischemia (TGCI).</p><p><b>METHODS</b>Gerbils were subjected to TGCI for 5 min. G. littoralis extract (GLE; 100 and 200 mg/kg) was administrated orally once daily for 7 days before ischemic surgery. Neuroprotection was examined by neuronal nuclear antigen immunohistochemistry and Fluoro-Jade B histofluorescence staining. Gliosis was observed by immunohistochemistry for glial fibrillary acidic protein and ionized calcium-binding adapter molecule 1. For neuroprotective mechanisms, immunohistochemistry for superoxide dismutase (SOD) 1 and brain-derived neurotrophic factor (BDNF) was done.</p><p><b>RESULTS</b>Pretreatment with 200 mg/kg of GLE protected pyramidal neurons in the cornu ammonis 1 (CA1) area from ischemic insult area (F = 29.770, P < 0.05) and significantly inhibited activations of astrocytes (F = 22.959, P < 0.05) and microglia (F = 44.135, P < 0.05) in the ischemic CA1 area. In addition, pretreatment with GLE significantly increased expressions of SOD1 (F = 28.561, P < 0.05) and BDNF (F = 55.298, P < 0.05) in CA1 pyramidal neurons of the sham- and ischemia-operated groups.</p><p><b>CONCLUSIONS</b>Our findings indicate that pretreatment with GLE can protect neurons from ischemic insults, and we suggest that its neuroprotective mechanism may be closely associated with increases of SOD1 and BDNF expressions as well as attenuation of glial activation.</p>
Résumé
Myelin degeneration is one of the characteristics of aging and degenerative diseases. This study investigated age-related alterations in expression of myelin basic protein (MBP) in the hippocampal subregions (dentate gyrus, CA2/3 and CA1 areas) of gerbils of various ages; young (1 month), adult (6 months) and aged (24 months), using western blot and immunohistochemistry. Western blot results showed tendencies of age-related reductions of MBP levels. MBP immunoreactivity was significantly decreased with age in synaptic sites of trisynaptic loops, perforant paths, mossy fibers, and Schaffer collaterals. In particular, MBP immunoreactive fibers in the dentate molecular cell layer (perforant path) was significantly reduced in adult and aged subjects. In addition, MBP immunoreactive mossy fibers in the dentate polymorphic layer and in the CA3 striatum radiatum was significantly decreased in the aged group. Furthermore, we observed similar age-related alterations in the CA1 stratum radiatum (Schaffer collaterals). However, the density of MBP immunoreactive fibers in the dentate granular cell layer and CA stratum pyramidale was decreased with aging. These findings indicate that expression of MBP is age-dependent and tissue specific according to hippocampal layers.
Sujets)
Adulte , Humains , Vieillissement , Technique de Western , Région CA1 de l'hippocampe , Gerbillinae , Hippocampe , Immunohistochimie , Protéine basique de la myéline , Gaine de myéline , Voie perforanteRésumé
<p><b>BACKGROUND</b>Oenanthe javanica (O. javanica) has been known to have high antioxidant properties via scavenging reactive oxygen species. We examined the effect of O. javanica extract (OJE) on antioxidant enzymes in the rat liver.</p><p><b>METHODS</b>We examined the effect of the OJE on copper, zinc-superoxide dismutase (SOD1), manganese superoxide dismutase (SOD2), catalase (CAT), and glutathione peroxidase (GPx) in the rat liver using immunohistochemistry and western blot analysis. Sprague-Dawley rats were randomly assigned to three groups; (1) normal diet fed group (normal-group), (2) diet containing ascorbic acid (AA)-fed group (AA-group) as a positive control, (3) diet containing OJE-fed group (OJE-group).</p><p><b>RESULTS</b>In this study, no histopathological finding in the rat liver was found in all the experimental groups. Numbers of SOD1, SOD2, CAT, and GPx immunoreactive cells and their protein levels were significantly increased in the AA-fed group compared with those in the normal-group. On the other hand, in the OJE-group, numbers of SOD1, SOD2, CAT, and GPx immunoreactive cells in the liver were significantly increased by about 190%, 478%, 685%, and 346%, respectively, compared with those in the AA-group. In addition, protein levels of SOD1, SOD2, CAT, and GPx in the OJE-group were also significantly much higher than those in the AA-group.</p><p><b>CONCLUSION</b>OJE significantly increased expressions of SOD1 and SOD2, CAT, and GPx in the liver cells of the rat, and these suggests that significant enhancements of endogenous enzymatic antioxidants by OJE might be a legitimate strategy for decreasing oxidative stresses in the liver.</p>
Sujets)
Animaux , Mâle , Rats , Antioxydants , Métabolisme , Acide ascorbique , Pharmacologie , Catalase , Métabolisme , Glutathione peroxidase , Métabolisme , Immunohistochimie , Foie , Métabolisme , Oenanthe , Chimie , Stress oxydatif , Extraits de plantes , Pharmacologie , Rat Sprague-Dawley , Superoxide dismutase , MétabolismeRésumé
<p><b>BACKGROUND</b>Water dropwort (Oenanthe javanica) as a popular traditional medicine in Asia shows various biological properties including antioxidant activity. In this study, we firstly examined the neuroprotective effect of Oenanthe javanica extract (OJE) in the hippocampal cornus ammonis 1 region (CA1 region) of the gerbil subjected to transient cerebral ischemia.</p><p><b>METHODS</b>Gerbils were established by the occlusion of common carotid arteries for 5 min. The neuroprotective effect of OJE was estimated by cresyl violet staining. In addition, 4 antioxidants (copper, zinc superoxide dismutase [SOD], manganese SOD, catalase, and glutathione peroxidase) immunoreactivities were investigated by immunohistochemistry.</p><p><b>RESULTS</b>Pyramidal neurons in the CA1 region showed neuronal death at 5 days postischemia; at this point in time, all antioxidants immunoreactivities disappeared in CA1 pyramidal neurons and showed in many nonpyramidal cells. Treatment with 200 mg/kg, not 100 mg/kg, OJE protected CA1 pyramidal neurons from ischemic damage. In addition, 200 mg/kg OJE treatment increased or maintained antioxidants immunoreactivities. Especially, among the antioxidants, glutathione peroxidase immunoreactivity was effectively increased in the CA1 pyramidal neurons of the OJE-treated sham-operated and ischemia-operated groups.</p><p><b>CONCLUSION</b>Our present results indicate that treatment with OJE can protect neurons from transient ischemic damage and that the neuroprotective effect may be closely associated with increased or maintained intracellular antioxidant enzymes by OJE.</p>
Sujets)
Animaux , Mâle , Antioxydants , Métabolisme , Utilisations thérapeutiques , Gerbillinae , Glutathione peroxidase , Métabolisme , Hippocampe , Métabolisme , Accident ischémique transitoire , Oenanthe , Chimie , Extraits de plantes , Utilisations thérapeutiquesRésumé
<p><b>BACKGROUND</b>Hippophae rhamnoides L. (HL) exerts antioxidant activities against various oxidative stress conditions. In this study, we investigated effects of extract from HL leaves (HLE) on cell proliferation and neuroblast differentiation in the subgranular zone (SGZ) of the dentate gyrus (DG) of aged gerbils.</p><p><b>METHODS</b>Aged gerbils (24 months) were divided into vehicle (saline)-treated- and HLE-treated-groups. The vehicle and HLE were orally administered with 200 mg/kg once a day for 20 days before sacrifice. Cell proliferation and neuroblast differentiation were examined in the DG using Ki67 and doublecortin (DCX), respectively. We also observed changes in immunoreactivities of superoxide dismutase 1 (SOD1) and superoxide dismutase 2 (SOD2), brain-derived neurotrophic factor (BDNF), and phospho-glycogen synthase kinase-3-beta (p-GSK-3β) to examine their relation with neurogenesis using immunohistochemistry.</p><p><b>RESULTS</b>The administration of HLE significantly increased the number of Ki67-positive cells and DCX-positive neuroblasts with well-developed processes in the SGZ of the DG of the HLE-treated-group. In addition, immunoreactivities of SOD1, SOD2, BDNF, and p-GSK-3β were significantly increased in granule and polymorphic cells of the DG in the HLE-treated-group compared with those in the vehicle-treated-group.</p><p><b>CONCLUSIONS</b>HLE treatment significantly increased cell proliferation and neuroblast differentiation, showing that immunoreactivities of SOD1, SOD2, BDNF, and p-GSK-3β were significantly increased in the DG. These indicate that increased neuroblast differentiation neurogenesis may be closely related to upregulation of SOD1, SOD2, BDNF, and p-GSK-3β in aged gerbils.</p>
Sujets)
Animaux , Mâle , Facteur neurotrophique dérivé du cerveau , Métabolisme , Différenciation cellulaire , Prolifération cellulaire , Gyrus denté , Métabolisme , Gerbillinae , Glycogen Synthase Kinase 3 , Métabolisme , Glycogen synthase kinase 3 beta , Hippophae , Métabolisme , Immunohistochimie , Facteur intrinsèque , Métabolisme , Neurogenèse , Superoxide dismutase , Métabolisme , Superoxide dismutase-1Résumé
<p><b>BACKGROUND</b>Oenanthe javanica is an aquatic perennial herb originated from East Asia. Nowadays, the effects of Oenanthe javanica have been proven in various disease models. Studies regarding the antioxidant effect of Oenanthe javanica in the kidney are still unclear.</p><p><b>METHODS</b>This study was therefore performed to investigate the effect of the Oenanthe javanica extract (OJE) in the rat kidney using immunohistochemistry for antioxidant enzymes, copper, zinc-superoxide dismutase (SOD1), manganese superoxide dismutase (SOD2), catalase (CAT) and glutathione peroxidase (GPx). Sprague-Dawley rats were randomly assigned to three groups: (1) normal diet fed-group (normal-group), (2) diet containing ascorbic acid (AA)-fed group (AA-group) as a positive control, (3) diet containing OJE-fed group (OJE-group). AA and OJE were supplied during 28 days.</p><p><b>RESULTS</b>The side-effects were not observed in all the groups. Immunoreactivities of SOD1, SOD2, CAT and GPx were easily detected in the distal tubules of the kidney, and their immunoreactivities in the AA-and OJE-groups were increased to about 1.4-1.5 times and 2 times, respectively, compared with those in the normal-group.</p><p><b>CONCLUSION</b>OJE significantly increased expressions of SOD1 & 2, CAT and GPx immunoreactivities in the distal tubules of the rat kidney, and this finding suggests that significant enhancements of endogenous enzymatic antioxidants by OJE treatment may be a legitimate strategy for decreasing oxidative stresses in the kidney.</p>
Sujets)
Animaux , Mâle , Rats , Antioxydants , Métabolisme , Catalase , Métabolisme , Glutathione peroxidase , Métabolisme , Rein , Métabolisme , Oenanthe , Chimie , Stress oxydatif , Extraits de plantes , Chimie , Pharmacologie , Rat Sprague-Dawley , Superoxide dismutase , MétabolismeRésumé
In the present study, we investigated the effect of Tetaus toxin (TeT) on cell proliferation and neuroblast differentiation using specific markers: 5-bromo-2-deoxyuridine (BrdU) as an exogenous marker for cell proliferation, Ki-67 as an endogenous marker for cell proliferation and doublecortin (DCX) as a marker for neuroblasts in the mouse hippocampal dentate gyrus (DG) after TeT treatment. Mice were intraperitoneally administered 2.5 and 10 ng/kg TeT and sacrificed 15 days after the treatment. In both the TeT-treated groups, no neuronal death occurred in any layers of the DG using neuronal nuclei (NeuN, a neuron nuclei maker) and Fluoro-Jade B (F-J B, a high-affinity fluorescent marker for the localization of neuronal degeneration). In addition, no significant change in glial activation in both the 2.5 and 10 ng/kg TeT-treated-groups was found by GFAP (a marker for astrocytes) and Iba-1 (a marker for microglia) immunohistochemistry. However, in the 2.5 ng/kg TeT-treated-group, the mean number of BrdU, Ki-67 and DCX immunoreactive cells, respectively, were apparently decreased compared to the control group, and the mean number of each in the 10 ng/kg TeT-treated-group was much more decreased. In addition, processes of DCX-immunoreactive cells, which projected into the molecular layer, were short compared to those in the control group. In brief, our present results show that low dosage (10 ng/kg) TeT treatment apparently decreased cell proliferation and neuroblast differentiation in the mouse hippocampal DG without distinct gliosis as well as any loss of adult neurons.