Deleting Mecp2 from the cerebellum rather than its neuronal subtypes causes a delay in motor learning in mice.

Rett syndrome is a devastating childhood neurological disorder caused by mutations in MECP2. Of the many symptoms, motor deterioration is a significant problem for patients. In mice, deleting Mecp2 from the cortex or basal ganglia causes motor dysfunction, hypoactivity, and tremor, which are abnormalities observed in patients. Little is known about the function of Mecp2 in the cerebellum, a brain region critical for motor function. Here we show that deleting Mecp2 from the cerebellum, but not from its neuronal subtypes, causes a delay in motor learning that is overcome by additional training. We observed irregular firing rates of Purkinje cells and altered heterochromatin architecture within the cerebellum of knockout mice. These findings demonstrate that the motor deficits present in Rett syndrome arise, in part, from cerebellar dysfunction. For Rett syndrome and other neurodevelopmental disorders, our results highlight the importance of understanding which brain regions contribute to disease phenotypes.

Reversal of Social Recognition Deficit in Adult Mice with MECP2 Duplication via Normalization of MeCP2 in the Medial Prefrontal Cortex.

Methyl-CpG binding protein 2 (MeCP2) is a basic nuclear protein involved in the regulation of gene expression and microRNA processing. Duplication of MECP2-containing genomic segments causes MECP2 duplication syndrome, a severe neurodevelopmental disorder characterized by intellectual disability, motor dysfunction, heightened anxiety, epilepsy, autistic phenotypes, and early death. Reversal of the abnormal phenotypes in adult mice with MECP2 duplication (MECP2-TG) by normalizing the MeCP2 levels across the whole brain has been demonstrated. However, whether different brain areas or neural circuits contribute to different aspects of the behavioral deficits is still unknown. Here, we found that MECP2-TG mice showed a significant social recognition deficit, and were prone to display aversive-like behaviors, including heightened anxiety-like behaviors and a fear generalization phenotype. In addition, reduced locomotor activity was observed in MECP2-TG mice. However, appetitive behaviors and learning and memory were comparable in MECP2-TG and wild-type mice. Functional magnetic resonance imaging illustrated that the differences between MECP2-TG and wild-type mice were mainly concentrated in brain areas regulating emotion and social behaviors. We used the CRISPR-Cas9 method to restore normal MeCP2 levels in the medial prefrontal cortex (mPFC) and bed nuclei of the stria terminalis (BST) of adult MECP2-TG mice, and found that normalization of MeCP2 levels in the mPFC but not in the BST reversed the social recognition deficit. These data indicate that the mPFC is responsible for the social recognition deficit in the transgenic mice, and provide new insight into potential therapies for MECP2 duplication syndrome.

The critical role of ASD-related gene CNTNAP3 in regulating synaptic development and social behavior in mice.

Accumulated genetic evidences indicate that the contactin associated protein-like (CNTNAP) family is implicated in autism spectrum disorders (ASD). In this study, we identified genetic mutations in the CNTNAP3 gene from Chinese Han ASD cohorts and Simons Simplex Collections. We found that CNTNAP3 interacted with synaptic adhesion proteins Neuroligin1 and Neuroligin2, as well as scaffolding proteins PSD95 and Gephyrin. Significantly, we found that CNTNAP3 played an opposite role in controlling the development of excitatory and inhibitory synapses in vitro and in vivo, in which ASD mutants exhibited loss-of-function effects. In this study, we showed that the male Cntnap3-null mice exhibited deficits in social interaction， spatial learning and prominent repetitive behaviors. These evidences elucidate the pivotal role of CNTNAP3 in synapse development and social behaviors, providing mechanistic insights into ASD.

Restoration of Mecp2 expression in GABAergic neurons is sufficient to rescue multiple disease features in a mouse model of Rett syndrome.

The postnatal neurodevelopmental disorder Rett syndrome, caused by mutations in MECP2, produces a diverse array of symptoms, including loss of language, motor, and social skills and the development of hand stereotypies, anxiety, tremor, ataxia, respiratory dysrhythmias, and seizures. Surprisingly, despite the diversity of these features, we have found that deleting Mecp2 only from GABAergic inhibitory neurons in mice replicates most of this phenotype. Here we show that genetically restoring Mecp2 expression only in GABAergic neurons of male Mecp2 null mice enhanced inhibitory signaling, extended lifespan, and rescued ataxia, apraxia, and social abnormalities but did not rescue tremor or anxiety. Female Mecp2(+/-) mice showed a less dramatic but still substantial rescue. These findings highlight the critical regulatory role of GABAergic neurons in certain behaviors and suggest that modulating the excitatory/inhibitory balance through GABAergic neurons could prove a viable therapeutic option in Rett syndrome.

Manipulations of MeCP2 in glutamatergic neurons highlight their contributions to Rett and other neurological disorders.

Many postnatal onset neurological disorders such as autism spectrum disorders (ASDs) and intellectual disability are thought to arise largely from disruption of excitatory/inhibitory homeostasis. Although mouse models of Rett syndrome (RTT), a postnatal neurological disorder caused by loss-of-function mutations in MECP2, display impaired excitatory neurotransmission, the RTT phenotype can be largely reproduced in mice simply by removing MeCP2 from inhibitory GABAergic neurons. To determine what role excitatory signaling impairment might play in RTT pathogenesis, we generated conditional mouse models with Mecp2 either removed from or expressed solely in glutamatergic neurons. MeCP2 deficiency in glutamatergic neurons leads to early lethality, obesity, tremor, altered anxiety-like behaviors, and impaired acoustic startle response, which is distinct from the phenotype of mice lacking MeCP2 only in inhibitory neurons. These findings reveal a role for excitatory signaling impairment in specific neurobehavioral abnormalities shared by RTT and other postnatal neurological disorders.

Feasibility and safety of continuous glucose monitoring systems in acute myocardial infarction subjects undergoing primary percutaneous coronary interventions.

PURPOSE: The purpose of this study was to evaluate the feasibility and safety of continuous glucose monitoring systems (CGMS) in ST segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary interventions (p-PCI) in coronary care units (CCU). METHODS: CGMS was performed for 3 days during CCU hospitalization for each of the subjects. The correlation between glucose values, recorded with CGMS, and finger-stick capillary glucose values was examined. The parameters and safety of CGMS were also investigated. RESULTS: Data from 219 subjects were included in the statistical analysis. Correlation analysis showed a strong positive correlation between interstitial glucose values recorded by CGMS and the corresponding capillary glucose values (P<0.001). The daytime mean blood glucose (MBG), the nighttime MBG and PT7.8 were the highest in the first day of CGMS compared with the second and third day. Furthermore, there were no indications of major hemorrhage or hematoma at the site of sensor insertion. Any adverse events were mild. CONCLUSIONS: CGMS glucose values are relatively accurate and reliable. CGMS were safe and can be used as a tool to detect trends in glucose levels and to predict upcoming glucose excursions in STEMI patients undergoing p-PCI.

Conditional deletion of Mecp2 in parvalbumin-expressing GABAergic cells results in the absence of critical period plasticity.

Mutations in the X-linked gene encoding the transcriptional modulator methyl-CpG-binding protein 2 (MeCP2) impair postnatal development of the brain. Here we use neuronal-type specific gene deletion in mice to show that conditional Mecp2 deletion in GABAergic parvalbumin-expressing (PV) cells (PV-Mecp2(-/y)) does not cause most Rett-syndrome-like behaviours, but completely abolishes experience-dependent critical period plasticity of primary visual cortex (V1) that develops normal visual functions. However, selective loss of Mecp2 in GABAergic somatostatin-expressing cells or glutamatergic pyramidal cells does not affect the critical period plasticity. MeCP2-deficient PV cells exhibit high intrinsic excitability, selectively reduced efficacy of recurrent excitatory synapses in V1 layer 4 circuits, and decreased evoked visual responses in vivo. Enhancing cortical gamma-aminobutyric acid (GABA) inhibition with diazepam infusion can restore critical period plasticity in both young and adult PV-Mecp2(-/y) mice. Thus, MeCP2 expression in inhibitory PV cells during the critical period is essential for local circuit functions underlying experience-dependent cortical plasticity.

Association of serum uric acid and coronary artery disease in premenopausal women.

OBJECTIVE: To date, no study in the published literature has investigated the role of various serum uric acid (SUA) concentrations in the development of angiographically-proven coronary artery disease (CAD) in premenopausal women. Therefore, the aim of this study was to investigate the role SUA levels may play in the prevalence, severity, and prognosis of CAD in premenopausal women. METHODS: This cross-sectional retrospective study included 607 premenopausal women who had undergone coronary angiography. The CAD diagnosis was based upon stenosis affecting ≥ 50% of the luminal diameter. Association of the SUA levels with CAD prevalence, severity, and clinical outcomes were assessed by statistical analysis. RESULTS: In total, 369 (60.8%) of the patients were diagnosed with CAD. The CAD patients had significantly higher SUA levels than those without CAD (5.3 ± 1.9 vs. 4.8 ± 1.7 mg/dL, P = 0.001). The SUA levels were found to be significantly associated with CAD prevalence (P = 0.013). Patients with higher levels of SUA also showed increased rates of multivessel disease and composite end-points, such as major adverse cardiac events. Furthermore, multivariate analysis identified abnormally high levels of uric acid (hyperuricemia) as an independent risk factor for CAD (OR 1.51 (1.11-2.53), P<0.05). CONCLUSIONS: The SUA levels are significantly associated with the prevalence of CAD. The SUA levels may be a predictor for incidence of major cardiovascular events in premenopausal women.

Effect of glycemic variability on short term prognosis in acute myocardial infarction subjects undergoing primary percutaneous coronary interventions.

OBJECTIVE: Glycemic variability (GV) still remains unclear whether acute glycemic excursion has the important prognostic significance in ST-segment elevation myocardial infarction (STEMI) patients undergoing p-PCI. So our aim is to assess the prognostic value of GV in STEMI patients undergoing p-PCI. METHODS: We studied 237 STEMI patients undergoing p-PCI, whose clinical and laboratory data were collected. We used a continuous glucose monitoring system (CGMS) to measure the fluctuations of blood glucose. Participants were grouped into diabetes group and non-diabetes group, and grouped into tertiles of mean amplitude of glycemic excursions (MAGE). The major adverse cardiac events (MACE) of patients was documented during in-hospital and 30-day follow-up. The relationship of MAGE and the incidence of MACE were analyzed. RESULTS: Data from 237 subjects were incorporated into the statistical analysis, a higher MAGE level was associated with the higher peak CK-MB values (r = 0.374, P <0.01), and the higher peak cTnI values (r = 0.410, P <0.01). The rate of composite MACE by MAGE tertiles (<2.37 mmol/l, 2.37-3.65 mmol/l and >3.65 mmol/l) was 7.5% vs. 14.1% vs. 22.8%, respectively (P = 0.025); STEMI patients with a higher MAGE level had a significantly higher non-IRA revascularization compared with those with lower MAGE levels (32% vs. 15% vs. 21%, P = 0.037). Moreover, diabetic patients with higher MAGE level had significantly higher incidence of composite MACE and non-IRA revascularization, non-diabetic subjects did not show the similar results. In multivariable logistic analysis, the independent predictors of MACE were: MBG, MAGE and LVEF in diabetic subjects and were MBG and MAGE in nondiabetic subjects. Other factors were not significantly associated with MACE. CONCLUSIONS: Greater GV is associated with composite MACE and non-IRA revascularization during in-hospital and 30-day follow-up in unadjusted analyses, especially for diabetic subjects. After multivariable logistic analysis, GV remains an independent prognostic factor for composite MACE in STEMI patients undergoing p-PCI.

Postinduction requirement of NMDA receptor activation for late-phase long-term potentiation of developing retinotectal synapses in vivo.

Spaced patterns of repetitive synaptic activation often result in a long-lasting, protein synthesis-dependent potentiation of synaptic transmission, known as late-phase long-term potentiation (L-LTP) that may serve as a substrate for long-term memory. Behavioral studies showed that posttraining blockade of NMDA subtype of the glutamate receptor (NMDAR) impaired long-term memory, although NMDAR activation is generally known to be required during LTP induction. In this study, we found that the establishment of L-LTP in vivo requires NMDAR activation within a critical time window after LTP induction. In the developing visual system of Xenopus laevis tadpole, L-LTP of retinotectal synapses could be induced by three episodes of theta burst stimulation (TBS) of the optic nerve with 5 min spacing ("spaced TBS"), but not by three TBS episodes applied en masse or spaced with intervals ≥10 min. Within a time window of ∼30 min after the spaced TBS, local perfusion of the tectum with NMDAR antagonist d-AP5 or Ca(2+)-chelator EGTA-AM impaired the establishment of L-LTP, indicating the requirement of postinduction activation of NMDAR/Ca(2+) signaling. Moreover, inhibiting spontaneous spiking activity in the tectum by local application of tetrodotoxin (TTX) prevented L-LTP when TTX was applied for 15 min immediately after the spaced TBS but not 1 h later, whereas the same postinduction TTX application in the retina had no effect. These findings offer new insights into the synaptic basis for the requirement of postlearning activation of NMDARs and point to the importance of postlearning spontaneous circuit activity in memory formation.

[Integrated treatment of traditional Chinese medicine and western medicine for early- and intermediate-stage diabetic nephropathy].

OBJECTIVE: To study the therapeutic effect of traditional Chinese herbal medicinal preparation Tangshenqing (TSQ) combined with alprostadil in the treatment of early- and intermediate-stage diabetic nephropathy (DN). METHODS: One hundred and twenty DN patients were randomized into 3 groups for different treatment protocols. The patients in the control group were given the basic treatment (low-protein diabetic diet and rigorous control of blood glucose, blood pressure, and blood fatty acid), and those in treatment group A received TSQ (containing Astragalus membranaceus, Panax notoginseng, Epimedium brevicornum, etc) in addition to the basic treatment, and those in treatment group B were treated with alprostadil injections (for 14 consecutive days) in addition to the treatment given in group A. Therapeutic effect evaluation was carried out after a 30-day treatment in all the patients. RESULTS: The overall efficaey rate of the treatment was 78.37% in the control group, 88.57% in the treatment group A, and 94.44% in treatment group B, suggesting better therapeutic effect in the latter two groups than in the control group (P<0.05). Patients in all the 3 groups exhibited symptomatic improvement of various degrees, but the treatment group B had the best results. After the treatments, the patients' blood glucose and fatty acids were lowered, without obvious difference between the 3 groups. Compared with the control group, the patients in the two treatment groups showed significant reduction in fibrinogen, 24-h urine microprotein and urine protein after the treatment (P<0.01 or 0.05). CONCLUSION: Combined use of traditional Chinese herbal medicine TSQ and alprostadil injections produces definite therapeutic effect on early- to intermediate-stage DN.