1.Vardenafil Increases Cell Proliferation in the Dentate Gyrus through Enhancement of Serotonin Expression in the Rat Dorsal Raphe.
Tae Soo KIM ; Il Gyu KO ; Yun Hee SUNG ; Sung Eun KIM ; Bo Kyun KIM ; Seung Kook PARK ; Mal Soon SHIN ; Chang Ju KIM ; Sang Jin YOON ; Khae Hawn KIM
Journal of Korean Medical Science 2009;24(6):1099-1104
This study was conducted to evaluate the effects of vardenafil (Levitra), a phosphodiesterase-5 (PDE-5) inhibitor, on cell proliferation in the hippocampal dentate gyrus and on 5-hyroxytryptamine (5-HT, serotonin) synthesis and tryptophan hydroxylase (TPH) expression in the rat dorsal raphe nucleus. Male Sprague-Dawley rats were divided into 6 groups (n=5 in each group): a control group, a 0.5 mg/kg-1 day vardenafil-treated group, a 1 mg/kg-1 day vardenafil-treated group, a 2 mg/kg-1 day vardenafil-treated group, a 1 mg/kg-3 day vardenafil-treated group, and a 1 mg/kg-7 day vardenafil-treated group. 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry was then performed to evaluate cell proliferation in the dentate gyrus. In addition, 5-HT and TPH immunohistochemistry was conducted to evaluate serotonin expression in the dorsal raphe. The results revealed that treatment with vardenafil increased cell proliferation in the dentate gyrus and enhanced 5-HT synthesis and TPH expression in the dorsal raphe in a dose- and duration-dependent manner. The findings demonstrate that the increasing effect of vardenafil on cell proliferation is closely associated with the enhancing effect of vardenafil on serotonin expression under normal conditions.
Animals
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Cell Proliferation/*drug effects
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*Dentate Gyrus/cytology/drug effects/metabolism
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Imidazoles/*pharmacology
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Male
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Phosphodiesterase Inhibitors/*pharmacology
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Piperazines/*pharmacology
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*Raphe Nuclei/cytology/drug effects/metabolism
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Rats
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Rats, Sprague-Dawley
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Serotonin/*biosynthesis
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Sulfones/pharmacology
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Triazines/pharmacology
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Tryptophan Hydroxylase/metabolism
2.Low Dose Radiation Overcomes Diabetes-induced Suppression of Hippocampal Neuronal Cell Proliferation in Rats.
Jin Oh KANG ; Sang Ki KIM ; Seong Eon HONG ; Taeck Hyun LEE ; Chang Ju KIM
Journal of Korean Medical Science 2006;21(3):500-505
We investigated the effect of low dose radiation on diabetes induced suppression of neurogenesis in the hippocampal dentate gyrus of rat. After 0.01 Gy, 0.1 Gy, 1 Gy and 10 Gy radiation was delivered, the dentate gyrus of hippocampus of streptozotocin (STZ)-induced diabetic rats were evaluated using immunohistochemistry for 5-bromo-2-deoxyuridine (BrdU), caspase-3, and terminal deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL) staining. The number of BrdU positive cells in the non-diabetic rats, diabetic rats without radiation, diabetic rats with 0.01 Gy radiation, diabetic rats with 0.1 Gy radiation, diabetic rats with 1 Gy radiation and diabetic rats with 10 Gy radiation were 55.4+/-8.5/mm2, 33.3+/-6.4/mm2, 67.7+/-10.5/mm2, 66.6+/-10.0/mm2, 23.5+/-6.3/mm2 and 14.3+/-7.2/mm2, respectively. The number of caspase-3 positive cells was 132.6+/-37.4/mm2, 378.6+/-99.1/mm2, 15.0+/-2.8/mm2, 57.1+/-16.9/mm2, 191.8+/-44.8/mm2 and 450.4+/-58.3/mm2, respectively. The number of TUNEL-positive cells was 24.5+/-2.0/mm2, 21.7+/-4.0/mm2, 20.4+/-2.0/mm2, 18.96+/-2.1/mm2, 58.3+/-7.9/mm2, and 106.0+/-9.8/mm2, respectively. These results suggest low doses of radiation paradoxically improved diabetes induced neuronal cell suppression in the hippocampal dentate gyrus of rat.
Rats, Sprague-Dawley
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Rats
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Radiotherapy/methods
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Neurons/*metabolism
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Male
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In Situ Nick-End Labeling
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Hippocampus/*cytology/metabolism/radiation effects
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Diabetes Mellitus, Experimental/radiotherapy
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Dentate Gyrus/drug effects/*radiation effects
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Cell Proliferation
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Caspase 3/metabolism
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Bromodeoxyuridine/pharmacology
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Apoptosis
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Animals
3.Extract Promotes Neurogenesis in the Hippocampal Dentate Gyrus of the Adult Mouse through Increasing Expressions of Brain-Derived Neurotrophic Factor and Tropomyosin-Related Kinase B.
Joon Ha PARK ; Bich Na SHIN ; Ji Hyeon AHN ; Jeong Hwi CHO ; Tae-Kyeong LEE ; Jae-Chul LEE ; Yong Hwan JEON ; Il Jun KANG ; Ki-Yeon YOO ; In Koo HWANG ; Choong Hyun LEE ; Yoo Hun NOH ; Sung-Su KIM ; Moo-Ho WON ; Jong Dai KIM
Chinese Medical Journal 2018;131(6):689-695
BackgroundGlehnia 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.
MethodsA 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.
ResultsTreatment 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.
ConclusionG. 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.
Animals ; Apiaceae ; chemistry ; Blotting, Western ; Brain-Derived Neurotrophic Factor ; metabolism ; Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Dentate Gyrus ; cytology ; drug effects ; Hippocampus ; cytology ; drug effects ; Immunohistochemistry ; Male ; Mice ; Microtubule-Associated Proteins ; metabolism ; Neurogenesis ; drug effects ; Neuropeptides ; metabolism ; Plant Extracts ; pharmacology ; Receptor, trkB ; metabolism
4.Alcohol-induced proliferation of neurons in mouse hippocampal dentate gyrus: a possible role of ceramide.
Tong-Xing DENG ; Zhi-Xin WANG ; Xiao-Qun GAO ; Yuan-Yuan SHI ; Zhan-You MA ; Hai-Xiao JIN ; Jin-Bo DENG
Acta Physiologica Sinica 2011;63(6):479-490
To investigate the role and mechanism of ceramide (Cer) regulation in alcohol-induced neuronal proliferation and the newborn neurons formation, we used sphingomyelin synthase 2 (predominant enzyme of Cer metabolism) knockout (SMS2(-/-)) and wild type (WT) female mice to establish the model of prenatal alcohol exposure. In 24 h after being given birth (postnatal day 0, P0), the offspring of model mice received blood sphingomyelin (SM) measurement with enzymatic method. On P0, P7, P14 and P30, the proliferation of granule cells in the dentate gyrus and newborn neurons were investigated with immunofluorescent labeling. The expression of protein kinase Cα (PKCα) in the hippocampus was tested with Western blot analysis. The results showed that the SM level of blood in SMS2(-/-) pups was significantly lower than that in WT pups. No matter in SMS2(-/-) or WT mice, the prenatal alcohol exposure down-regulated the SM levels in pups with dose-dependency. In both SMS2(-/-) and WT pups, the number of proliferative neurons and newborn neurons in the dentate gyrus gradually decreased with the growing age. Compared with the WT pups, SMS2(-/-) pups showed significantly more proliferative neurons and newborn neurons in the dentate gyrus. Notably, prenatal alcohol exposure dose-dependently increased proliferative neurons and newborn neurons in the dentate gyrus in both WT and SMS2(-/-) pups. The hippocampal expression of PKCα protein in SMS2(-/-) mice was lower than that in WT mice, and prenatal alcohol exposure could up-regulate the PKCα protein expression in both WT and SMS2(-/-) mice with dose dependency. These results suggest that alcohol exposure during pregnancy can induce the compensatory neural cell proliferation and the production of newborn neurons in offspring, and the Cer-ceramide-1-phosphate (C1P) pathway is involved in alcohol-induced neural cell proliferation. The activation of PKCα may be a key step to start the Cer-C1P pathway and up-regulate the alcohol-induced neural cell proliferation and the newborn neurons formation.
Animals
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Animals, Newborn
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Cell Proliferation
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drug effects
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Cells, Cultured
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Ceramides
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metabolism
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Dentate Gyrus
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cytology
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Ethanol
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toxicity
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Female
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Mice
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Mice, Knockout
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Neurons
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cytology
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Pregnancy
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Prenatal Exposure Delayed Effects
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physiopathology
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Protein Kinase C-alpha
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metabolism
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Signal Transduction
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Transferases (Other Substituted Phosphate Groups)
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genetics