OBJECTIVE: To observe the expression of discs large homolog 4 (DLG4) protein in hippocampus, amygdala and frontal cortex of rats and evaluate postsynaptic density in heroin dependence. METHODS: The rat heroin dependent model was established by increasing intraperitoneal injection of heroin. DLG4 proteins in hippocampus, amygdala and frontal cortex of heroin dependent 9, 18, 36 days rats were detected with immunohistochemical staining and compared with that in the control group. RESULTS: DLG4 proteins in hippocampus, amygdala and frontal cortex were gradually reduced with extension of heroin dependent time. CONCLUSION Heroin dependence can affect postsynaptic density of hippocampus, amygdala and frontal cortex. The changes become more apparent with extension of heroin dependence time.
Amygdala/metabolism* ; Animals ; Disks Large Homolog 4 Protein ; Frontal Lobe/metabolism* ; Heroin/pharmacology* ; Heroin Dependence ; Hippocampus/metabolism* ; Injections, Intraperitoneal ; Intracellular Signaling Peptides and Proteins/metabolism* ; Membrane Proteins/metabolism* ; Rats

To investigated the mechanisms underlying the effects of modified Kaixin San(MKXS) on improving memory and synaptic damage of Alzheimer's disease(AD) mouse model with conditional presenilin 1/2 conditional double knockout(PS cDKO). Specifically, 60 PS cDKO mice(3-3.5 months old) and their age-matched wild-type(WT) littermates were randomized into three groups: WT group(n=20), PS cDKO group(n=20), and PS cDKO+MKXS group(n=20). Mice in WT and PS cDKO groups were fed with standard chow and those in PS cDKO+MKXS group were given chow containing MKXS(at 2.55 g·kg~(-1)) for 60 days. Novel object reco-gnition task was employed to detect the recognition memory of mice, and Western blot to detect the protein levels of synapse-associated proteins in the hippocampus(HPC) of mice, such as NR1, NR2 A, NR2 B, p-αCaMKⅡ, tau, and p-tau. Microglial morphology in the HPC CA1 of mice was observed based on immunohistochemistry. Quantitative real time-PCR(qRT-PCR) was employed to detect the mRNA levels of the pro-inflammatory factors and synapse-associated proteins in the HPC of mice, including COX-2, iNOS, IL-1β, IL-6, TNF-α, PSD95, NR1, NR2 A, NR2 B, and MAP2. The protein levels of IL-1β, TNF-α, and IL-6 were tested by enzyme-linked immunosorbent assay(ELISA). The interaction between PSD95 and αCaMKⅡ and between PSD95 and p-αCaMKⅡ was tested by co-immunoprecipitation(Co-IP). The results showed that PS cDKO+MKXS demonstrated significantly higher preference index and recognition index of the new objects, lower protein level of p-tau(ser 396/404) and mRNA levels of COX-2, iNOS, TNF-α, IL-1β, and IL-6 in HPC, higher protein levels of NR1, NR2 A, NR2 B, and p-αCaMKⅡ and mRNA levels of NR1, NR2 A, NR2 B, PSD95, and MAP2, and stronger interaction of αCaMKⅡ with PSD95 and interaction of p-αCaMKⅡ with PSD95 than the PS cDKO group. Immunohistoche-mical staining showed that MKXS inhibited the activation of microglia. In conclusion, MKXS improves memory and synaptic damage in mice with AD by modulating αCaMKⅡ-PSD95 protein binding through inhibition of neuroinflammation.
Animals ; Mice ; Alzheimer Disease/genetics* ; Disks Large Homolog 4 Protein/metabolism* ; Neuroinflammatory Diseases ; Tumor Necrosis Factor-alpha/metabolism* ; Cyclooxygenase 2/metabolism* ; Interleukin-6/metabolism* ; Protein Binding ; Mice, Knockout ; Hippocampus/metabolism* ; Disease Models, Animal ; RNA, Messenger/metabolism*

OBJECTIVETo explore the effect mechanism of electroacupuncture (EA) at Changqiang (GV 1) or Baihui (GV 20) on autism based on molecular biology.

METHODSThe autism model was established by intraperitoneal injection of sodium valproate (VPA) in Wistar pregnant rats. Forty young rats with autism were selected and randomly divided into a model group, a non-acupoint group, an electroacupuncture at "Changqiang" (GV 1) (EAGV 1 for short) group and an electroacupuncture at "Baihui" (GV 20) (EAGV 20 for short) group. Another 10 normal young rats were selected as a blank group. In the EAGV 1 group, acupuncture was applied at Houhai [as Changqiang (GV 1)], then EA apparatus was connected with continuous wave, 2 Hz, 20 min, once a day for consecutive 20 days. The same EA manipulation as EAGV 1 group was used in the EAGV 20 group where "Baihui" (GV 20) was selected and non-acupoint group where non-acupoint in the right rib was selected. Blank group and model group were reared under the same conditions without any intervention. The escape latency and the ratio of swimming distance in platform quadrant to total swimming distance in each group were observed by using Morris water maze, and the PSD-95 protein expression in hippocampal CA 1 was measured by immunohistochemical techniques.

RESULTSCompared with the blank group, the escape latency in the model group and the non-acupoint group lengthened (both P < 0.05), the ratio of swimming distance in platform quadrant to total swimming distance was decreased (both P < 0.05), the PSD-95 protein expression was decreased (P < 0.05). Compared with the model group, the escape latency in the EAGV 1 group and the EAGV 20 group were decreased (both P < 0.05), the ratio of swimming distance in platform quadrant to total swimming distance was increased, the PSD-95 protein expression was increased (both P < 0.05). But the escape latency, the ratio of swimming distance in platform quadrant to total swimming distance and the PSD-95 protein expression had no significant difference between EAGV 1 group and EAGV 20 group (P > 0.05).

CONCLUSIONElectroacupuncture at Changqiang (GV 1) or Baihui (GV 20) can respectively improve learning and memory ability of rats with autism, which has no significant difference and the mechanism of action may be related to regulation of the PSD-95 protein expression.

Acupuncture Points ; Acupuncture Therapy ; Animals ; Autistic Disorder ; genetics ; metabolism ; psychology ; therapy ; Disks Large Homolog 4 Protein ; Electroacupuncture ; Female ; Hippocampus ; metabolism ; Humans ; Intracellular Signaling Peptides and Proteins ; genetics ; metabolism ; Learning ; Male ; Membrane Proteins ; genetics ; metabolism ; Memory ; Rats ; Rats, Wistar

OBJECTIVETo observe the effects of PSD95 gene specific siRNAs on neuropathic pain relief, neuron viability, and postsynaptic calcium/calmodulin-dependent protein kinase IIα (CaMKIIα) phosphorylation in vitro and in vivo.

METHODSGene-specific siRNAs of rat PSD95 were synthesized chemically for transfection. Adult male Sprague-Dawley (SD) rats were randomly divided into 3 groups: naïve group (n=6), sham group (n=6), and sciatic nerve chronic constriction injury (CCI) group (n=24). The CCI group was further divided into 4 groups (n=6 in each group), which were pretreated with normal saline, transfection vehicle, negative control siRNAs, and PSD95 gene specific siRNAs respectively. All the subgroups received corresponding agents intrathecally for 3 days, started one day before the CCI of sciatic nerve. Both mechanical allodynia and thermal hyperalgesia were measured on post-operative day 3 and 7. PSD95 gene silenced NG108-15 cells were further stimulated by glutamate, with the cell viability and the expression/phosphorylation of CaMKIIα measured by MTT cell proliferation assay and Western blot, respectively.

RESULTSThe siRNAs decreased PSD95 mRNA level significantly both in vivo and in vitro. Neuropathic pain rats pretreated with PSD95 gene specific siRNAs exhibited significant elevation in the mechanical withdrawal threshold and paw withdrawal thermal latency, without affecting the baseline nociception. PSD95 gene silencing enhanced neuronal tolerance against the glutamate excitotoxicity, meanwhile the phosphorylation of CaMKIIα Thr286 was attenuated.

CONCLUSIONPre-emptive administration of PSD95 gene specific siRNAs may attenuate the central sensitization CaMKIIα-related signaling cascades, leading to the relief of neuropathic pain.

Animals ; Calcium-Calmodulin-Dependent Protein Kinase Type 2 ; metabolism ; Cells, Cultured ; Disks Large Homolog 4 Protein ; Intracellular Signaling Peptides and Proteins ; genetics ; Male ; Membrane Proteins ; genetics ; Neuralgia ; therapy ; Neurons ; physiology ; Phosphorylation ; RNA, Small Interfering ; genetics ; Rats ; Rats, Sprague-Dawley

To detect the effect of PDZ1, domain of postsynaptic density 95 (PSD-95), on apoptosis of hippocampal neurons induced by oxygen-glucose deprivation (OGD), Sprague-Dawley rat hippocampal neurons were infected with PDZ1-viruses after 21 days of plating. Twenty-four hours after infection, cells were treated with OGD for 1.5 h, then were incubated with DAPI and apoptosis-like cells were characterized, or were collected for co-immunoprecipitation and Western blot analyses. The results showed that: (1) PDZ1 overexpression was observed in hippocampal neurons; (2) Apoptosis induced by OGD was obviously decreased in neurons overexpressing PDZ1 (P<0.05); (3) Overexpression of PDZ1 prevented the binding of GluR6 to PSD-95; (4) Overexpression of PDZ1 inhibited MLK3 and JNK1/2 activation induced by OGD. These results indicate that overexpression of PDZ1 may prevent hippocampal neurons from apoptosis induced by OGD.
Animals ; Apoptosis ; Cells, Cultured ; Culture Media ; chemistry ; Disks Large Homolog 4 Protein ; Glucose ; chemistry ; Hippocampus ; cytology ; Intracellular Signaling Peptides and Proteins ; metabolism ; Membrane Proteins ; metabolism ; Neurons ; cytology ; pathology ; Oxygen ; chemistry ; PDZ Domains ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo observe the effect of curcumin on the expression of synapse-related proteins PSD-95 and Shank1 in APP/PS1 double transgenic mice.

METHODThree-month-old APP/PS1 dtg mice were randomly divided into the model group, the positive Rosiglitazone control group and curcumin high (400 mg x kg(-1) x d(-1)), medium (200 mg x kg(-1) x d(-1)) and low (100 mg x kg(-1) x d(-1)) dose groups, with non-genetically modified mice with the same background as the normal group. After the oral administration for three months, immunohistochemistry and Western blot were adopted for detection.

RESULTAccording to the behavioral detection, the treatment group and the model group showed differences in the place navigation test and the spatial probe test to varying degrees (P < 0.01 or P < 0.05). The expression of PSD-95 and Shank1-positive cells of hippocampus CA1 region significantly decreased in model mice compared with normal control group (P < 0.01); while the curcumin intervention group showed recovery to some extend. Western blot results showed that the strap of PSD-95 protein expression became significantly thinner and lighter in the model group compared with the normal control group (P < 0.01); while the curcumin intervention group showed notably thicker and darker straps of PSD-95 protein expression (P < 0.05).

CONCLUSIONCurcumin can increase the expression of synapse-related proteins PSD95 and Shank1 in APP/PS1 double transgenic mice, improve structure and plasticity of synapse in APP/PS1 double transgenic mice and enhance their learning and memory abilities.

Amyloid beta-Protein Precursor ; genetics ; Animals ; CA1 Region, Hippocampal ; drug effects ; metabolism ; Curcumin ; pharmacology ; Disks Large Homolog 4 Protein ; Gene Expression Regulation ; drug effects ; Guanylate Kinases ; metabolism ; Membrane Proteins ; metabolism ; Mice ; Mice, Transgenic ; Nerve Tissue Proteins ; metabolism ; Presenilin-1 ; genetics ; Synapses ; drug effects ; metabolism

OBJECTIVETo investigate the effect of cerebral X-ray irradiation on learning and memory function in young rats.

METHODSFifty-four SD rats aged 35 d were randomly divided into 3 groups with 18 in each group: rats in 3-d group and 7-d group received X-ray irradiation with a dose of 28.5 mGy/d for 3 d and 7 d, respectively; rats in control group received sham X-ray irradiation. Morris water maze (MWM) was tested when animals at age of 60 d; then the animals were sacrificed and brain samples were taken. The neurodegeneration was observed by Fluro-Jade B staining; the expression of N-methyl-aspartate (NMDA) receptors subunit 2B (NR2B) and postsynaptic density protein-95 (PSD-95) in the hippocampus were analyzed by immunofluorescence and Western blot methods, respectively, and ultrastructure of CA1 region was observed with electron microscopy.

RESULTSNo significant difference in 1-4 d escape latency as shown in MWM test was noted between 3d group and control group (P>0.05); while the escape latency in 7d group was significantly longer than that in control group (P<0.01). No significant differences in lingering in the quadrant and the frequency of passing through the original platform between 3-d group and control group (P>0.05), while those in 7-d group were significantly lower than those in control group (P<0.01). Compared to control group, the number of FJB positive cells in 7-d group was increased (P<0.01); the expressions of NR2B and PSD-95 in hippocampus CA1 region were also increased (P<0.05). The ultrastructure observation in 7-d group showed that the synapse structure of some neurons was impaired.

CONCLUSIONX-ray irradiation may affect learning and memory function of young rats, which is associated with overexpression of NR2B and PSD-95 in hippocampal regions.

Animals ; Brain ; radiation effects ; CA1 Region, Hippocampal ; metabolism ; radiation effects ; Disks Large Homolog 4 Protein ; Intracellular Signaling Peptides and Proteins ; metabolism ; Learning ; radiation effects ; Membrane Proteins ; metabolism ; Memory ; radiation effects ; Neurons ; Rats ; Rats, Sprague-Dawley ; Receptors, N-Methyl-D-Aspartate ; metabolism ; Synapses ; X-Rays

OBJECTIVETo investigate the effects of sodium ferulate (SF), an intravenous drug made from traditional Chinese herbs, on activation of postsynaptic density-95 (PSD-95) and neuroprotection after transient cerebral artery occlusion in rats.

METHODSForty-six male Sprague-Dawley rats were randomized into 2 groups (n=23 in each group): the control group and the SF group. After anesthesia, the middle cerebral artery occlusion (MCAO) was conducted with the intraluminal filament technique. The neurological deficit was assessed with the method devised by Bederson et al. The 2,3,4-triphenyltetrazolium chloride staining was used to assess the infarct volume. We adopted a modified six-point scale to conduct neurobehavioral evaluation. Immediately the activation of postsynaptic density-95 (PSD-95) was studied with Western blot analysis system in the cortex and striatum of rat brain.

RESULTSThe neurologic deficit score of the SF group decreased substantially compared with that of the control group (P<0.05). The infarct volume of the control group (168.1 mm3 +/- 42.2 mm3) was significantly larger than that of the SF group (61.5 mm3 +/- 28.7 mm3) at 24 hours after reperfusion (P<0.01). And the rats showed some neurological deficit. The activity of PSD-95 in the SF group at most timepoints was less than that in the control group. No upregulation of PSD-95 protein could be detected in the contralateral cortex.

CONCLUSIONSSodium ferulate can induce a neuroprotective effect against the transient focal cerebral ischemic injury and weaken the activation of PSD-95 in ischemic area after MCAO.

Animals ; Blotting, Western ; Brain Infarction ; drug therapy ; etiology ; Coumaric Acids ; therapeutic use ; Disks Large Homolog 4 Protein ; Intracellular Signaling Peptides and Proteins ; drug effects ; metabolism ; Ischemic Attack, Transient ; complications ; drug therapy ; metabolism ; Male ; Membrane Proteins ; drug effects ; metabolism ; Neuroprotective Agents ; therapeutic use ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Treatment Outcome

OBJECTIVETo investigate the relationship between the excitotoxicity and serum-inducible kinase (SNK) and spine-associated Rap GTPase-activating protein (SPAR) pathway in primary hippocampal neuron injury induced by glutamate and furthermore, to explore the molecular mechanism of neuroprotection of Zibu Piyin Recipe (ZBPYR) and the relationship between ZBPYR and the morphological regulation of dendritic spines.

METHODSThe serum containing ZBPYR was prepared by seropharmacology. Reverse transcription and polymerase chain reaction (RT-PCR) was used to detect the expression of mRNA for SNK, SPAR, postsynaptic density protein 95 (PSD-95) and N-methyl-D-aspartate (NMDA) receptor subunits (NR1, NR2A and NR2B) in primary rat hippocampal neuron cultures after pretreatment with 10 micromol/L glutamate and ZBPYR serum.

RESULTSZBPYR serum pretreatment resulted in a significant down-regulation of glutamate-induced SNK mRNA expression (P<0.05). Significant up-regulation was seen on the mRNA expression of SPAR and PSD-95 (P<0.05). All these changes were dose-dependent. The mRNA expression of NR1, NR2A and NR2B was down-regulated to different degrees (P<0.05).

CONCLUSIONThe mechanism of effect of ZBPYR on glutamate-induced excitotoxicity may be related to the regulation of SNK-SPAR signal pathway. ZBPYR may play a role in protecting and maintaining the normal morphology and structure of dendritic spines, which may be achieved by inhibiting the excessive activation of NMDA receptors.

Animals ; Cells, Cultured ; Disks Large Homolog 4 Protein ; Drugs, Chinese Herbal ; pharmacology ; GTPase-Activating Proteins ; genetics ; metabolism ; Gene Expression Regulation ; drug effects ; Glutamic Acid ; toxicity ; Hippocampus ; drug effects ; enzymology ; pathology ; Intracellular Signaling Peptides and Proteins ; genetics ; metabolism ; Membrane Proteins ; genetics ; metabolism ; Neurons ; drug effects ; enzymology ; pathology ; Protein Kinases ; genetics ; metabolism ; Protein-Serine-Threonine Kinases ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptors, N-Methyl-D-Aspartate ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Serum