Genetic analysis of a pregnant woman with moderate intellectual disability due to variant of DLG4 gene / 中华医学遗传学杂志

OBJECTIVE@#To carry out genetic testing and prenatal diagnosis for a woman featuring moderate intellectual disability (ID).@*METHODS@#The patient had presented at the First Affiliated Hospital of Zhengzhou University on April 28, 2021. With informed consent, peripheral blood and amniotic fluid samples were collected for the extraction of genomic DNA. Pathogenic copy number variations (CNVs) were detected with CNV-seq, and single gene variants were detected by whole exome sequencing (WES) and Sanger sequencing. Candidate variant was verified by Sanger sequencing, and CNV-seq and multiplex ligation-dependent probe amplification (MLPA) were used to detect fetal CNVs.@*RESULTS@#The 23-year-old woman had moderate ID, sideway walking, and unstable holding. Ultrasonography at 18+3 weeks' gestation had revealed no fetal abnormality. No pathogenic CNV was detected in the woman by CNV-Seq, while WES revealed that she has harbored a heterozygous c.1675C>T (p.Arg559*) variant of the DLG4 gene, which was verified by Sanger sequencing. Based on guidelines from the American College of Medical Genetics and Genomics, the variant was predicted to be likely pathogenic (PVS1+PM2_supporting). Sanger sequencing has confirmed that the fetus has inherited this variant, and CNV-Seq also revealed that that fetus has harbored a 0.1 Mb heterozygous deletion at Xp21.1, which has encompassed the DMD gene, and the result was verified by MLPA.@*CONCLUSION@#The heterozygous c.1675C>T variant of the DLG4 gene probably underlay the mental retardation in this woman, and her fetus was found to harbor the same variant in addition with deletion of the DMD gene, which may predispose to ID type 62.

Association analysis of genetic variant of rs13331 in PSD95 gene with autism spectrum disorders: A case-control study in a Chinese population / 华中科技大学学报（医学）（英德文版）

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by high heritability. Recently, autism, the most profound form of ASD, has been increasingly attributed to synaptic abnormalities. Postsynaptic density 95 (PSD95), encoding PSD protein-95, was found essential for synaptic formation, maturation and plasticity at a PSD of excitatory synapse. It is possibly a crucial candidate gene for the pathogenesis of ASD. To identify the relationship between the rs13331 of PSD95 gene and ASD, we performed a case-control study in 212 patients and 636 controls in a Chinese population by using a polymerase chain reaction-restriction fragment length polymerase (PCR-RFLP) assay. The results showed that in genetic analysis of the heterozygous model, an association between the T allele of the rs13331 and ASD was found in the dominant model (OR=1.709, 95% CI 1.227-2.382, P=0.002) and the additive model (OR=1.409, 95% CI=1.104-1.800, P=0.006). Our data indicate that the genetic mutation C>T at the rs13331 in the PSD95 gene is strikingly associated with an increased risk of ASD.

Effect of Heroin on DLG4 Expression in Hippocampus, Amygdala and Frontal Cortex of Rats / 法医学杂志

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.

Effect of cerebral X-ray irradiation on learning and memory function in young SD rats / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effect of cerebral X-ray irradiation on learning and memory function in young rats.</p><p><b>METHODS</b>Fifty-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.</p><p><b>RESULTS</b>No 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.</p><p><b>CONCLUSION</b>X-ray irradiation may affect learning and memory function of young rats, which is associated with overexpression of NR2B and PSD-95 in hippocampal regions.</p>

Effects of electroacupuncture at different acupoints on learning and memory ability and PSD-95 protein expression on hippocampus CA1 in rats with autism / 中国针灸

<p><b>OBJECTIVE</b>To explore the effect mechanism of electroacupuncture (EA) at Changqiang (GV 1) or Baihui (GV 20) on autism based on molecular biology.</p><p><b>METHODS</b>The 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.</p><p><b>RESULTS</b>Compared 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).</p><p><b>CONCLUSION</b>Electroacupuncture 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.</p>

Effect of curcumin on synapse-related protein expression of APP/PS1 double transgenic mice / 中国中药杂志

<p><b>OBJECTIVE</b>To observe the effect of curcumin on the expression of synapse-related proteins PSD-95 and Shank1 in APP/PS1 double transgenic mice.</p><p><b>METHOD</b>Three-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.</p><p><b>RESULT</b>According 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).</p><p><b>CONCLUSION</b>Curcumin 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.</p>

PSD95 gene specific siRNAs attenuate neuropathic pain through modulating neuron sensibility and postsynaptic CaMKIIα phosphorylation / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To 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.</p><p><b>METHODS</b>Gene-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.</p><p><b>RESULTS</b>The 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.</p><p><b>CONCLUSION</b>Pre-emptive administration of PSD95 gene specific siRNAs may attenuate the central sensitization CaMKIIα-related signaling cascades, leading to the relief of neuropathic pain.</p>

Effects of Zibu Piyin recipe on SNK-SPAR pathway in neuron injury induced by glutamate / 中国结合医学杂志

<p><b>OBJECTIVE</b>To 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.</p><p><b>METHODS</b>The 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.</p><p><b>RESULTS</b>ZBPYR 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).</p><p><b>CONCLUSION</b>The 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.</p>

Overexpression of PDZ1 domain of PSD-95 protein rescues hippocampal neurons from apoptosis induced by oxygen-glucose deprivation / 生理学报

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.

Neuroprotective effect of sodium ferulate on transient focal cerebral ischemia by weakening activation of postsynaptic density-95 in rats / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To 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.</p><p><b>METHODS</b>Forty-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.</p><p><b>RESULTS</b>The 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.</p><p><b>CONCLUSIONS</b>Sodium 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.</p>