OBJECTIVETo investigate the role of Bcl-2 in the cytoprotective effect of thyroid hormone against hippocampal cell apoptosis in rats with chronic cerebral ischemia.

METHODSFifty adult male SD rats were randomized into sham-operated group, 2-vessel occlusion (2VO) group and triiodothyronine (T3) treatment group. At 7 and 14 days after the operation, the tissue structure of the CA1 region was observed with Nissl staining, and TUNEL staining was used to determine the apoptosis index (AI) in the dentate gyrus; Western blotting was performed to detect the expression level of Bcl-2 in the hippocampus.

RESULTSIn the 2VO group, the CA1 region of the hippocampus showed obvious structural damages with reduced number of neurons, and these changes were significantly improved in T3 treatment group. At 7 days after the operation, no significant difference was found in AI between the sham-operated group (17.714∓2.553), 2VO group (20.868∓2.090) and T3 group (20.365∓1.055) (P=0.060); the expression level of Bcl-2 was higher in T3 group than in 2VO group. On day 14, AI was 66.532∓3.249 in 2VO group, significantly higher than that in T3 treatment group (56.153∓4.556, P=0.001); Bcl-2 expression was the highest in T3 group and the lowest in 2VO group.

CONCLUSIONThyroid hormone can reduce cell apoptosis in the hippocampus of rats with chronic cerebral ischemia possibly by up-regulating the expression of Bcl-2.

Animals ; Apoptosis ; drug effects ; Brain Ischemia ; pathology ; CA1 Region, Hippocampal ; cytology ; pathology ; Male ; Neurons ; cytology ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rats ; Rats, Sprague-Dawley ; Triiodothyronine ; pharmacology

OBJECTIVETo determine 5-lipoxygenase (5-LOX) expression and the effect of zileuton, a selective 5-LOX inhibitor,on hippocampal neuron injury induced by global cerebral ischemia in rats.

METHODSGlobal cerebral ischemia was induced by bilateral common carotid artery occlusion combined with hypotension in rats. 5-LOX expression was detected by Western blot analyses and 5-LOX localization was visualized by immunohistochemistry and double immunofluorescence methods. The 5-LOX inhibitor zileuton (10, 30, 50 mg/kg) was orally administered for 3 d after ischemia.

RESULTSThe 5-LOX expression was increased in the ischemic hippocampus on d1-7 (peaked at d3), and 5-LOX protein was primarily localized in neurons and translocated to the nuclei in the hippocampal CA1 region after ischemia. The 5-LOX inhibitor zileuton (30, 50 mg/kg) reduced ischemia-induced hippocampal neurons death 3d after ischemia.

CONCLUSION5-LOX is involved in global cerebral ischemic damage in rats, and the 5-LOX inhibitor zileuton has a protective effect on neuronal damage in the rat hippocampus following global cerebral ischemia.

Animals ; Arachidonate 5-Lipoxygenase ; metabolism ; physiology ; Brain Ischemia ; metabolism ; pathology ; CA1 Region, Hippocampal ; metabolism ; pathology ; Disease Models, Animal ; Hydroxyurea ; analogs & derivatives ; pharmacology ; Lipoxygenase Inhibitors ; pharmacology ; Male ; Neurons ; drug effects ; pathology ; Rats ; Rats, Sprague-Dawley

OBJECTIVEKetogenic diet (KD) is a high fat, low protein, low carbohydrate diet. Its antiepileptic effect is certain but the underlying mechanism is unknown. The aim of the study was to reveal the possible mechanism from the view points of synaptic reorganization and GluR(5) expression in hippocampus.

METHODSEpilepsy was induced in Sprague-Dawley rats by kainic acid at postnatal day 28, all control animals were fed with normal rodent chow, whereas experimental rats were fed with ketogenic feed for 8 weeks. Spontaneous recurrent seizures were recorded. Mossy fiber sprouting and neuron damage in hippocampus were investigated by Timm staining and Nissl staining. Western blot and RT-PCR methods were applied to detect the expression of GluR(5) and GluR(5) mRNA in hippocampus.

RESULTSKD-fed rats (1.40 +/- 1.03) had significantly fewer spontaneous recurrent seizures than control diet-fed rats (7.36 +/- 3.75). The mean A of mossy fiber sprouting in the inner molecular layer of dentate gyrus was markedly higher in KA induced animals than that in saline control animals but it was similar in different diet fed groups. No significant differences were found in the mean A of Timm staining in CA(3) area and Nissl staining of neuron in hilus, CA(3) and CA(1) area. After KA kindling, KD-fed animals [(189.38 +/- 40.03)/mg pro] had significantly higher GluR(5) expression in hippocampus than control diet-fed animals [(128.79 +/- 46.51)/mg pro] although their GluR(5) mRNA was the same.

CONCLUSIONMossy fiber sprouting may be responsible for epileptogenesis in KA induced model and KD can suppress seizures in these animals. KD may upregulate young rat GluR(5) in inhibitory interneurons of CA(1) thus lead to an increased inhibition to prevent the propagation of seizure.

Animals ; Blotting, Western ; CA1 Region, Hippocampal ; metabolism ; pathology ; CA3 Region, Hippocampal ; metabolism ; pathology ; Chromosome Pairing ; drug effects ; Dentate Gyrus ; metabolism ; pathology ; Diet, Ketogenic ; methods ; Disease Models, Animal ; Epilepsy ; chemically induced ; diet therapy ; genetics ; metabolism ; pathology ; Excitatory Amino Acid Agonists ; Hippocampus ; drug effects ; metabolism ; pathology ; Kainic Acid ; Male ; Mossy Fibers, Hippocampal ; metabolism ; pathology ; Pyramidal Cells ; metabolism ; pathology ; RNA, Messenger ; metabolism ; Rats ; Receptors, Kainic Acid ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo study the effects of astragalan (AG) on the expression of the neural cell adhesion molecule(NCAM) and c-fos of hippocampus CA1 region after the ischemic brain injury in rats.

METHODSOne hundred male Wistar rats (180-220 g) were divided into ten groups randomly, they were sham operated group (SOG, n = 10), three model group(MG-ld, 3d, 7d, n = 10), as well as three low and high dose astragalan treatment groups (L/H-AGTG-1d, 3d, 7d, n = 10), respectively. And then, middle cerebral artery of MG and AGTG were intercepted by operation inducing brain injured. Their cerebral blood vessel were reperfused on 1, 2, 3 d, respectively, after the L/H-AGTG were treated with the AG (5 mg/kg and 15 mg/kg, ip). After neurologic impairment(NIP) was scored, animals were decapitated to take out hippocampus for counting apoptosis , determining the expression of the NCAM and c-fos by immunohistochemistry method and RT-PCR semiquantitative analysis, respectively.

RESULTSThe NIP scores and apoptotic cell of the L-AGTG and H-AGTG were significantly lower than MG (P < 0.05 or P < 0.01). The expression of NCAM and c-fos were significantly higher than the MG (P < 0.05 or P < 0.01).

CONCLUSIONAstragalan could improve significantly neural function of ischemia brain injury in rats,the mechanism concerned probably with blocking or reversing apoptosis of hippocampus by promoting the expression of the NCAM and c-fos of hippocampus CA1 region.

Animals ; Apoptosis ; drug effects ; Astragalus membranaceus ; chemistry ; Brain Ischemia ; metabolism ; pathology ; CA1 Region, Hippocampal ; cytology ; Kaempferols ; pharmacology ; Male ; Neural Cell Adhesion Molecules ; metabolism ; Neurons ; drug effects ; Neuroprotective Agents ; pharmacology ; Polysaccharides ; pharmacology ; Rats ; Rats, Wistar

OBJECTIVETo observe the effect of a Chinese medicine compound, Naoerkang (NEK), on amyloid-beta peptide (1-42; Aβ(1-42)) and matrix metalloproteinase-9 (MMP-9) expressions in the hippocampus of Alzheimer's disease (AD) model rats.

METHODSA total of 48 male Sprague Dawley (SD) rats were randomly divided into normal control, untreated, and piracetam groups, and low-dose, medium-dose, and high-dose NEK groups, with 8 rats in each group. The 5-μL aggregated Aβ(1-42) (2 μg/μL) were injected into both CA1 areas of the hippocampus in the rats to establish an AD model, whereas the normal control was treated with the same dose of normal saline. The rats in the NEK groups were treated with a high, medium, or low dose of NEK [60 g/(kg·d), 30 g/(kg·d), and 15 g/(kg·d)], respectively, intragastrically for 28 days; piracetam (0.375 g/kg, intragastrically) was consecutively administered in the piracetam group; and normal saline was applied in the normal control and untreated groups. A Y-maze test was used for behavioral study to test the learning and memory abilities. Aβ(1-42) and MMP-9 expressions in the hippocampus was determined immunohistochemically, and the results were analyzed by image acquisition and an analysis system.

RESULTSAggregated Aβ(1-42) induced obvious learning and memory dysfunction, as well as up-regulation of Aβ(1-42) expression in the hippocampus. Compared with those in the normal control group, the learning and memory abilities of rats in the untreated group significantly decreased (P<0.01), and the expression of Aβ(1-42) was significantly increased (P<0.01). Twenty-eight days after different treatments, compared with those in the untreated group, the learning and memory abilities of AD model rats in the piracetam, low-dose, medium-dose and high-dose NEK groups were significantly improved (P<0.01 or P<0.05), and the expression of Aβ(1-42) in the hippocampus decreased (P<0.01 or P<0.05), and MMP-9 increased (P<0.01 or P<0.05), especially in the high-dose NEK group.

CONCLUSIONNEK might play a role of anti-dementia by increasing the expression of MMP-9 in the hippocampus of AD model rats, resulting in the reduction of the quantity of Aβ(1-42) and improvement in learning and memory ability in AD model rats.

Alzheimer Disease ; drug therapy ; metabolism ; pathology ; physiopathology ; Amyloid beta-Peptides ; metabolism ; Animals ; CA1 Region, Hippocampal ; drug effects ; enzymology ; pathology ; physiopathology ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Hippocampus ; drug effects ; metabolism ; pathology ; physiopathology ; Immunohistochemistry ; Male ; Matrix Metalloproteinase 9 ; metabolism ; Memory ; drug effects ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the diversify of the nuclear pathway of c-Jun NH2-terminal kinases (JNK) during transient brain ischemia/reperfusion injury in hippocampal neuron apoptosis in spontaneously hypertensive rats (SHR) and to test whether the neuroprotection of curcumine on transient brain ischemia/reperfusion injury in SHR is related to the nuclear pathway of JNK.

METHODSMale Wistar-Kyoto (WKY) rats and SHR were randomly divided into five groups (n = 6): WKY sham group (W-Sham), WKY ischemia/reperfusion group (W-I/ R), SHR sham group (S-Sham), SHR ischemia/reperfusion group (S-I/R) and SHR curcumine (a chinese traditional medicine)100 mg/kg treatment group (S-Cur), which were sacrificed at 2 h, 6 h, 24 h, 3 d and 7 d after reperfusion. Global brain ischemic model was established by 4-VO method. The TdT-mediated dUTP nick end labeling (TUNEL) method was used to detect the neuron apoptosis in hippocampal CA1 region. The immunohistochemical method was applied to investigate the expressions of c-jun and c-fos in hippocampal CA1 region.

RESULTSThe expressions of apoptosis and c-jun and c-fos in CA1 region in S-Sham group, W-I/R group and S-I/R group were more than those in W-Sham group (P < 0.05), were significantly increased in S-I/R group than those in W-I/R group (P < 0.05), and were significantly decreased in S-Cur group than those in S-I/R group (P < 0.05).

CONCLUSIONNeuronal apoptosis and the expressions of c-jun and c-fos are more in SHR hippocampal. Global brain ischemia/reperfusion injury induces more expressions of apoptosis in hippocampal neuron in SHR, and the more expressions of c-jun and c-fos may participate in that process. The neuroprotection of curcumine in SHR is related to c-jun and c-fos.

Animals ; Apoptosis ; drug effects ; Brain Ischemia ; metabolism ; pathology ; CA1 Region, Hippocampal ; drug effects ; metabolism ; Curcumin ; pharmacology ; JNK Mitogen-Activated Protein Kinases ; metabolism ; Male ; Neurons ; drug effects ; metabolism ; Proto-Oncogene Proteins c-fos ; metabolism ; Rats ; Rats, Inbred SHR ; Rats, Inbred WKY ; Reperfusion Injury ; metabolism ; pathology

OBJECTIVETo explore the protection of high intensity microwave radiation on hypothalamo-pituitary-adrenal axis (HPAA) activity and hippocampal CA1 structure in rats and the protectiveeffect of Qindan Granule (QG) on radiation injured rats.

METHODSTotally 48 Wistar rats were randomlydivided into 8 groups, i.e., the normal control group, post-radiation day 1, 7, and 10 groups, 7 and 10days prevention groups, day 7 and 10 treatment groups, 6 in each group. Rats in prevention groups wererespectively administered with QG liquid (1 mL/100 g, 4. 75 g crude drugs) for 7 days and 10 days bygastrogavage and then microwave radiation. Then preventive effect for radiation injury was statisticallycalculated with the normal control group and the post-radiation day 1 group. Rats in treatment groupswere firstly irradiated, and then administered with QG liquid (1 mL/100 g, 4.75 g crude drugs). Finally preventive effect for radiation injury was statistically calculated with the normal control group, post-radiation day 7 and 10 groups. Contents of corticotrophin releasing hormone (CRH), beta endorphin (beta-EP), adrenocorticotropic hormone (ACTH), and heat shock protein 70 (HSP70) were detected. Morphological changes and structure of hippocampal CA1 region were observed under light microscope.

RESULTSCompared with the normal control group, contents of CRH and beta-EP significantly decreased in each radiation group. Serum contents of ACTH and beta-EP significantly increased in post-radiation day 1 and 7 groups (P < 0.05). Compared with radiation groups, beta-EP content in serum and pituitary significantly increased, and serum ACTH content significantly decreased in prevention groups (P < 0.05). Pituitary contents of CRH and beta-EP significantly increased in prevention groups. Serum contents of ACTH, beta-EP, and HSP70 were significantly lower in day 7 treatment group than post-radiation day 7 group (P < 0.05). Morphological results showed that pyramidal neurons in the hippocampal CA1 region arranged in disorder, with swollen cells, shrunken and condensed nucleus, dark dyeing cytoplasm, unclear structure. Vessels in partial regions were dilated with static blood; tissues were swollen and sparse. In prevention and treatment groups pathological damage of hippocampal CA1 region was obviously attenuated; neurons were arranged more regularly; swollen, pycnotic, or deleted neuron number were decreased; vascular dilatation and congestion was lessened.

CONCLUSIONQG could affect HPAA function and activity of high intensity microwave radiated rats, showing certain preventive and therapeutic effects of microwave radiated rats by adjusting synthesis and release of partial bioactive peptides and hormones in HPAA, improving pathological injury in hippocampal CA1 region.

Adrenocorticotropic Hormone ; blood ; Animals ; CA1 Region, Hippocampal ; drug effects ; pathology ; radiation effects ; Corticotropin-Releasing Hormone ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; HSP70 Heat-Shock Proteins ; blood ; Hypothalamo-Hypophyseal System ; drug effects ; radiation effects ; Microwaves ; adverse effects ; Pituitary-Adrenal System ; drug effects ; radiation effects ; Random Allocation ; Rats ; Rats, Wistar ; beta-Endorphin ; blood ; metabolism

OBJECTIVETo investigate the neuroprotective effect of basic fibroblast growth factor (bFGF) on neurological function after hypoxic-ischemic brain damage (HIBD) in neonatal rats.

METHODSNinety-six HIBD models of neonatal Wistar rats were made by shearing right arteria carotis communis and then breathing 8% O(2)+92%N(2) for two hours. The models were divided into two groups randomly: the bFGF trial group and the normal saline control group. Each group had forty-eight rats. The other forty-eight neonatal Wistar rats were taken into the sham operation group. Forty rats were taken from each group and sacrificed on the 4 th, 7 th, 10 th, 17 th and 24 th days after the operation, respectively, The pathological changes in the brain were observed by optical microscope and the expressions of nestin and growth-associated protein-43 (GAP-43) in hippocampal CA1 region were examined with immunohistochemical staining and image quantitative analysis on the 4 th, 7 th, 10 th, 17 th and 24 th days after the operation. The spatial cognitive capability of other eight rats which were taken from each group respectively was evaluated by using the Morris water maze at the age of 30 days.

RESULTS(1) No brain damage was found in the sham operation group, the neurocytes were degenerative and necrotic in the control group of normal saline. The pathological manifestation of the brain damage in the bFGF trial group was milder than that of the normal saline control group. (2) Expression of nestin: The number of nestin-positive cells in hippocampal CA1 region of control group on the 4 th, 7 th, 10 th, 17 th and 24 th days after the operation was significantly increased compared with that of the sham operation group at all time points, and the numbers of nestin-positive cells in hippocampal CA1 region of the trial group were higher than those of the sham operation group and the control group (P < 0.01). (3) The expression of GAP-43 in hippocampal CA1 region of the neonatal rats reached peak on the 10th day after the operation in all the three groups. The integral optical density (IOD) of GAP-43 in hippocampal CA1 region of the control group was higher than that of the sham-operation group at all time points, and the IOD of GAP-43 in hippocampal CA1 region of the trial group was higher than those of the sham operation group and the control group at all time points (P < 0.01 for all). (4) The latency to escape platform in control group (51.75 +/- 11.27s) was longer than that in trial group (40.32 +/- 11.48s) and the sham operation group (36.58 +/- 10.83s) (P < 0.05); the frequency of passing through the platform in control group (2.34 +/- 2.42) was less than that in trial group (5.08 +/- 3.86) and the sham operation group (7.03 +/- 3.62) (P < 0.05). There was no significant difference between the trial group and the sham operation group (P > 0.05).

CONCLUSIONS(1) The expression of nestin and GAP-43 increased in hippocampal CA1 region of neonatal rats with HIBD, it may be involved in the activation of neural stem cells and the regeneration of neurocytes after HIBD. (2) The treatment with bFGF can improve the ability of learning and memory of neonatal rats with HIBD. (3) Exogenous bFGF could enhance the expression of nestin and GAP-43 in the brain of neonatal rats with HIBD, which may play an important role in restoration of neurons damaged due to hypoxia-ischemia.

Animals ; Animals, Newborn ; Brain ; drug effects ; pathology ; CA1 Region, Hippocampal ; pathology ; Fibroblast Growth Factor 2 ; therapeutic use ; GAP-43 Protein ; therapeutic use ; Hippocampus ; drug effects ; Hypoxia, Brain ; prevention & control ; Hypoxia-Ischemia, Brain ; prevention & control ; Intermediate Filament Proteins ; metabolism ; Ischemia ; prevention & control ; Maze Learning ; drug effects ; Nerve Tissue Proteins ; metabolism ; Nestin ; Neurons ; drug effects ; physiology ; Rats ; Rats, Wistar

OBJETIVETo investigate the neuroprotective effects and underlying mechanisms of salvianolic acid B (Sal B) extracted from Salvia miltiorrhiza on hippocampal CA1 neurons in mice with cerebral ischemia reperfusion injury.

METHODSForty male National Institute of Health (NIH) mice were randomly divided into 4 groups with 10 animals each, including the sham group, the model group, the SalB group (SalB 22.5 mg/kg) and the nimodipine (Nim) group (Nim 1 mg/kg). A mouse model of cerebral ischemia and reperfusion injury was established by bilateral carotid artery occlusion for 30 min followed by 24-h reperfusion. The malondialdehyde (MDA) content, the nitric oxide synthase (NOS) activity, the superoxide dismutase (SOD) activity and total antioxidant capability (T-AOC) of the pallium were determined by biochemistry methods. The morphologic changes and Bcl-2 and Bax protein expression in hippocampal CA1 neurons were observed by using hematoxylineosin staining and immunohistochemistry staining, respectively.

RESULTSIn the SalB group, the MDA content and the NOS activity of the pallium in cerebral ischemia-reperfusion mice significantly decreased and the SOD activity and the T-AOC significantly increased, as compared with the model group (P<0.05 or P<0.01). The SalB treatment also rescued neuronal loss (P<0.01) in the hippocampal CA1 region, strongly promoted Bcl-2 protein expression (P<0.01) and inhibited Bax protein expression (P<0.05).

CONCLUSIONSSalB increases the level of antioxidant substances and decreases free radicals production. Moreover, it also improves Bcl-2 expression and reduces Bax expression. SalB may exert the neuroprotective effect through mitochondria-dependent pathway on hippocampal CA1 neurons in mice with cerebral ischemia and reperfusion injury and suggested that SalB represents a promising candidate for the prevention and treatment of ischemic cerebrovascular disease.

Animals ; Antioxidants ; pharmacology ; therapeutic use ; Benzofurans ; chemistry ; pharmacology ; therapeutic use ; Brain Ischemia ; complications ; drug therapy ; CA1 Region, Hippocampal ; pathology ; Cell Count ; Immunohistochemistry ; Male ; Malondialdehyde ; metabolism ; Mice ; Neurons ; drug effects ; pathology ; Nitric Oxide Synthase ; metabolism ; Reperfusion Injury ; complications ; drug therapy ; Superoxide Dismutase ; metabolism ; bcl-2-Associated X Protein ; metabolism

This study is to investigate the effects of paeoniflorin on cerebral blood flow and the balance of PGI2/TXA2 of rats with focal cerebral ischemia-reperfusion injury. A total of 72 SD rats (3) were randomly divided into 6 groups: sham operation group, cerebral ischemia-reperfusion model group (I/R gourp), low (10 mg.kg-1), middle (20 mg.kg-1) and high (40 mg.kg-1) doses of paeoniflorin groups and nimrnodipine group. Focal cerebral ischemia in rats was made by inserting a monofilament suture into internal carotid artery for 90 min and then reperfused for 24 h. The effects of paeoniflorin on neurological deficit scores and the infarction volume of brain were detected. Relative regional cerebral blood flow (rCBF) was continuously monitored over ischemic hemispheres by laser-Doppler flowmetry (LDF). The expression of COX-2 in hippocampal CAl region was estimated by immunohistochemistry and the contents of prostacyclin I2 (PGI2), thromboxane A2 (TXA2), and ratio of PGIJ2/TXA2 in serum were measured by ELISA kits. Paeoniflorin significantly ameliorated neurological scores, reduced the infarction volume, and increased regional cerebral blood flow relative to the I/R group. In addition, paeoniflorin could inhibit COX-2 expression and the release of TXA2 and prevent the downregulation of PGI2 induced by I/R injury. The neuroprotective effects of paeoniflorin against focal cerebral ischemia-reperfusion rats might be attributed to improve the supply of injured hemisphere blood flow and adjust the balance between PGI2/TXA2.
6-Ketoprostaglandin F1 alpha ; blood ; Animals ; Brain ; blood supply ; CA1 Region, Hippocampal ; metabolism ; Cyclooxygenase 2 ; metabolism ; Glucosides ; isolation & purification ; pharmacology ; Infarction, Middle Cerebral Artery ; blood ; metabolism ; pathology ; physiopathology ; Male ; Monoterpenes ; isolation & purification ; pharmacology ; Neuroprotective Agents ; isolation & purification ; pharmacology ; Paeonia ; chemistry ; Plants, Medicinal ; chemistry ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Regional Blood Flow ; drug effects ; Reperfusion Injury ; metabolism ; physiopathology ; Thromboxane B2 ; blood