Publications by authors named "Cuiping Tian"

18 Publications

  • Page 1 of 1

Rational Remodeling of Atypical Scaffolds for the Design of Photoswitchable Cannabinoid Receptor Tools.

J Med Chem 2021 Sep 3. Epub 2021 Sep 3.

iHuman Institute, ShanghaiTech University, Pudong, Shanghai 201210, China.

Azobenzene-embedded photoswitchable ligands are the widely used chemical tools in photopharmacological studies. Current approaches to azobenzene introduction rely mainly on the isosteric replacement of typical azologable groups. However, atypical scaffolds may offer more opportunities for photoswitch remodeling, which are chemically in an overwhelming majority. Herein, we investigate the rational remodeling of atypical scaffolds for azobenzene introduction, as exemplified in the development of photoswitchable ligands for the cannabinoid receptor 2 (CB2). Based on the analysis of residue-type clusters surrounding the binding pocket, we conclude that among the three representative atypical arms of the CB2 antagonist, AM10257, the adamantyl arm is the most appropriate for azobenzene remodeling. The optimizing spacer length and attachment position revealed with excellent thermal bistability, decent photopharmacological switchability between its two configurations, and high subtype selectivity. This structure-guided approach gave new impetus in the extension of new chemical spaces for tool customization for increasingly diversified photo-pharmacological studies and beyond.
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http://dx.doi.org/10.1021/acs.jmedchem.1c01088DOI Listing
September 2021

Multiregional profiling of the brain transmembrane proteome uncovers novel regulators of depression.

Sci Adv 2021 Jul 21;7(30). Epub 2021 Jul 21.

iHuman Institute, ShanghaiTech University, Shanghai 201210, China.

Transmembrane proteins play vital roles in mediating synaptic transmission, plasticity, and homeostasis in the brain. However, these proteins, especially the G protein-coupled receptors (GPCRs), are underrepresented in most large-scale proteomic surveys. Here, we present a new proteomic approach aided by deep learning models for comprehensive profiling of transmembrane protein families in multiple mouse brain regions. Our multiregional proteome profiling highlights the considerable discrepancy between messenger RNA and protein distribution, especially for region-enriched GPCRs, and predicts an endogenous GPCR interaction network in the brain. Furthermore, our new approach reveals the transmembrane proteome remodeling landscape in the brain of a mouse depression model, which led to the identification of two previously unknown GPCR regulators of depressive-like behaviors. Our study provides an enabling technology and rich data resource to expand the understanding of transmembrane proteome organization and dynamics in the brain and accelerate the discovery of potential therapeutic targets for depression treatment.
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http://dx.doi.org/10.1126/sciadv.abf0634DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8294761PMC
July 2021

Organized cannabinoid receptor distribution in neurons revealed by super-resolution fluorescence imaging.

Nat Commun 2020 11 11;11(1):5699. Epub 2020 Nov 11.

iHuman Institute, ShanghaiTech University, 201210, Shanghai, China.

G-protein-coupled receptors (GPCRs) play important roles in cellular functions. However, their intracellular organization is largely unknown. Through investigation of the cannabinoid receptor 1 (CB), we discovered periodically repeating clusters of CB hotspots within the axons of neurons. We observed these CB hotspots interact with the membrane-associated periodic skeleton (MPS) forming a complex crucial in the regulation of CB signaling. Furthermore, we found that CB hotspot periodicity increased upon CB agonist application, and these activated CB displayed less dynamic movement compared to non-activated CB. Our results suggest that CB forms periodic hotspots organized by the MPS as a mechanism to increase signaling efficacy upon activation.
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http://dx.doi.org/10.1038/s41467-020-19510-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7659323PMC
November 2020

Protective effects of syringin against oxidative stress and inflammation in diabetic pregnant rats via TLR4/MyD88/NF-κB signaling pathway.

Biomed Pharmacother 2020 Nov 26;131:110681. Epub 2020 Aug 26.

Department of Obstetrics, Women & Children`s Health Care Hospital of Linyi, No. 1, Qinghe South Road, Luozhuang District, Linyi City, Shandong Province, 276017, China. Electronic address:

Gestational diabetes (GDM) is common in pregnancies due to the inflammation and oxidative stress-mediated insulin resistance. In the present study, GDM was induced in the Wistar rats by administering the streptozotocin to elucidate whether the administration of syringin (50 mg/kg/day) during pregnancy could improve maternal glycemia and protect against the complications of GDM. The animals were assessed for their morphological changes in the β-islets of Langerhans and their insulin-producing ability, inflammatory cytokine markers, and the involvement of TLR4/MyD88/NF-κB signaling pathway using RT-PCR. The results demonstrated that the onset of GDM demonstrated pancreatic tissue degeneration in the islets of Langerhans with a significant increase in oxidative stress and reduced antioxidant enzymes. Besides, the mRNA expression levels of TLR4, MyD88, NF-Kβ p65; NLRP3 mRNA were profoundly increased in GDM rats compared to normal pregnant rats. On the other hand, syringin administered GDM rats abrogated the oxidative stress and attenuated the level of the inflammatory cytokines. Intriguingly, the decrease in TLR4 expression and the downstream molecules of MyD88, NF-κB, and NLRP3 were also observed in syringin administered GDM rats that indicate the insulin secretion stimulatory actions of syringin through the suppression of TLR4 signaling. These novel findings of the study provide evidence that syringin could be a probable candidate to be used in the treatment of gestational diabetes in the future.
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http://dx.doi.org/10.1016/j.biopha.2020.110681DOI Listing
November 2020

Hybrid Spectral Library Combining DIA-MS Data and a Targeted Virtual Library Substantially Deepens the Proteome Coverage.

iScience 2020 Mar 12;23(3):100903. Epub 2020 Feb 12.

iHuman Institute, ShanghaiTech University, Shanghai 201210, China; School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China. Electronic address:

Data-independent acquisition mass spectrometry (DIA-MS) is a powerful technique that enables relatively deep proteomic profiling with superior quantification reproducibility. DIA data mining predominantly relies on a spectral library of sufficient proteome coverage that, in most cases, is built on data-dependent acquisition-based analysis of the same sample. To expand the proteome coverage for a pre-determined protein family, we report herein on the construction of a hybrid spectral library that supplements a DIA experiment-derived library with a protein family-targeted virtual library predicted by deep learning. Leveraging this DIA hybrid library substantially deepens the coverage of three transmembrane protein families (G protein-coupled receptors, ion channels, and transporters) in mouse brain tissues with increases in protein identification of 37%-87% and peptide identification of 58%-161%. Moreover, of the 412 novel GPCR peptides exclusively identified with the DIA hybrid library strategy, 53.6% were validated as present in mouse brain tissues based on orthogonal experimental measurement.
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http://dx.doi.org/10.1016/j.isci.2020.100903DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7044796PMC
March 2020

Calcineurin Signaling Mediates Disruption of the Axon Initial Segment Cytoskeleton after Injury.

iScience 2020 Feb 1;23(2):100880. Epub 2020 Feb 1.

School of Life Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Pudong New District, Shanghai 201210, China. Electronic address:

The axon initial segment (AIS) cytoskeleton undergoes rapid and irreversible disruption prior to cell death after injury, and loss of AIS integrity can produce profound neurological effects on the nervous system. Here we described a previously unrecognized mechanism for ischemia-induced alterations in AIS integrity. We show that in hippocampal CA1 pyramidal neurons Na1.6 mostly preserves at the AIS after disruption of the cytoskeleton in a mouse model of middle cerebral artery occlusion. Genetic removal of neurofascin-186 leads to rapid disruption of Na1.6 following injury, indicating that neurofascin is required for Na1.6 maintenance at the AIS after cytoskeleton collapse. Importantly, calcineurin inhibition with FK506 fully protects AIS integrity and sufficiently prevents impairments of spatial learning and memory from injury. This study provides evidence that calcineurin activation is primarily involved in initiating disassembly of the AIS cytoskeleton and that maintaining AIS integrity is crucial for therapeutic strategies to facilitate recovery from injury.
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http://dx.doi.org/10.1016/j.isci.2020.100880DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7031317PMC
February 2020

Second messenger ApA polymerizes target protein HINT1 to transduce signals in FcεRI-activated mast cells.

Nat Commun 2019 10 11;10(1):4664. Epub 2019 Oct 11.

State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China.

Signal transduction systems enable organisms to monitor their external environments and accordingly adjust the cellular processes. In mast cells, the second messenger ApA binds to the histidine triad nucleotide-binding protein 1 (HINT1), disrupts its interaction with the microphthalmia-associated transcription factor (MITF), and eventually activates the transcription of genes downstream of MITF in response to immunostimulation. How the HINT1 protein recognizes and is regulated by ApA remain unclear. Here, using eight crystal structures, biochemical experiments, negative stain electron microscopy, and cellular experiments, we report that ApA specifically polymerizes HINT1 in solution and in activated rat basophilic leukemia cells. The polymerization interface overlaps with the area on HINT1 for MITF interaction, suggesting a possible competitive mechanism to release MITF for transcriptional activation. The mechanism depends precisely on the length of the phosphodiester linkage of ApA. These results highlight a direct polymerization signaling mechanism by the second messenger.
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http://dx.doi.org/10.1038/s41467-019-12710-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6789022PMC
October 2019

Critical role of spectrin in hearing development and deafness.

Sci Adv 2019 04 17;5(4):eaav7803. Epub 2019 Apr 17.

iHuman Institute, ShanghaiTech University, Shanghai, China.

Inner ear hair cells (HCs) detect sound through the deflection of mechanosensory stereocilia. Stereocilia are inserted into the cuticular plate of HCs by parallel actin rootlets, where they convert sound-induced mechanical vibrations into electrical signals. The molecules that support these rootlets and enable them to withstand constant mechanical stresses underpin our ability to hear. However, the structures of these molecules have remained unknown. We hypothesized that αII- and βII-spectrin subunits fulfill this role, and investigated their structural organization in rodent HCs. Using super-resolution fluorescence imaging, we found that spectrin formed ring-like structures around the base of stereocilia rootlets. These spectrin rings were associated with the hearing ability of mice. Further, HC-specific, βII-spectrin knockout mice displayed profound deafness. Overall, our work has identified and characterized structures of spectrin that play a crucial role in mammalian hearing development.
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http://dx.doi.org/10.1126/sciadv.aav7803DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6469942PMC
April 2019

Differential roles of Na1.2 and Na1.6 in regulating neuronal excitability at febrile temperature and distinct contributions to febrile seizures.

Sci Rep 2018 01 15;8(1):753. Epub 2018 Jan 15.

State Key Laboratory of Cognitive Neuroscience and Learning, School of Brain and Cognitive Sciences, the Collaborative Innovation Center for Brain Science, Beijing Normal University, Beijing, China.

Dysregulation of voltage-gated sodium channels (VGSCs) is associated with multiple clinical disorders, including febrile seizures (FS). The contribution of different sodium channel subtypes to environmentally triggered seizures is not well understood. Here we demonstrate that somatic and axonal sodium channels primarily mediated through Na1.2 and Na1.6 subtypes, respectively, behave differentially at FT, and might play distinct roles in FS generation. In contrast to sodium channels on the main axonal trunk, somatic ones are more resistant to inactivation and display significantly augmented currents, faster gating rates and kinetics of recovery from inactivation at FT, features that promote neuronal excitabilities. Pharmacological inhibition of Na1.2 by Phrixotoxin-3 (PTx3) suppressed FT-induced neuronal hyperexcitability in brain slice, while up-regulation of Na1.2 as in Na1.6 knockout mice showed an opposite effect. Consistently, Na1.6 knockout mice were more susceptible to FS, exhibiting much lower temperature threshold and shorter onset latency than wildtype mice. Neuron modeling further suggests that Na1.2 is the major subtype mediating FT-induced neuronal hyperexcitability, and predicts potential outcomes of alterations in sodium channel subtype composition. Together, these data reveal a role of native Na1.2 on neuronal excitability at FT and its important contribution to FS pathogenesis.
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http://dx.doi.org/10.1038/s41598-017-17344-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5768682PMC
January 2018

Differential Proteomics Analysis of Colonic Tissues in Patients of Slow Transit Constipation.

Biomed Res Int 2016 30;2016:4814702. Epub 2016 Apr 30.

Zhongnan Hospital of Wuhan University, Department of Colorectal & Anal Surgery, Clinical Center of Intestinal and Colorectal Diseases of Hubei Province, Key Laboratory of Intestinal & Colorectal Diseases of Hubei Province, Wuhan University, No. 169, Donghu Road, Wuchang District, Wuhan, Hubei 430071, China.

Objective. To investigate and screen the different expression of proteins in STC and normal group with a comparative proteomic approach. Methods. Two-dimensional electrophoresis was applied to separate the proteins in specimens from both 5 STC patients and 5 normal controls. The proteins with statistically significant differential expression between two groups were identified by computer aided image analysis and matrix assisted laser desorption ionization tandem time of flight mass spectrometry (MALDI-TOF-MS). Results. A total of 239 protein spots were identified in the average gel of the normal control and 215 in patients with STC. A total of 197 protein spots were matched and the mean matching rate was 82%. There were 14 protein spots which were expressed with statistically significant differences from others. Of those 14 protein spots, the expression of 12 spots increased markedly, while that of 2 spots decreased significantly. Conclusion. The proteomics expression in colonic specimens of STC patients is statistically significantly different from that of normal control, which may be associated with the pathogenesis of STC.
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http://dx.doi.org/10.1155/2016/4814702DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4867068PMC
February 2017

Ultraviolet-enhanced supercontinuum generation in uniform photonic crystal fiber pumped by a giant-chirped fiber laser.

Opt Express 2014 Oct;22(20):24697-705

We report on an ultraviolet-enhanced supercontinuum generation in a uniform photonic crystal fiber pumped by a giant-chirped mode-locked Yb-doped fiber laser. We find theoretically and experimentally that the initial pluses with giant chirp leads more initial energy transferred to the dispersive waves in visible and ultraviolet wavelength. An extremely wide optical spectrum spanning from 370 nm to beyond 2400 nm with a broad 3 dB spectral bandwidth of 367 nm (from 431 nm to 798 nm) is obtained. Over 36% (350 mW) of the total output power locates in the visible and ultraviolet regime between 370 nm and 850 nm with a maximum spectral power density of 1.6 mW/nm at 550 nm.
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http://dx.doi.org/10.1364/OE.22.024697DOI Listing
October 2014

Molecular identity of axonal sodium channels in human cortical pyramidal cells.

Front Cell Neurosci 2014 23;8:297. Epub 2014 Sep 23.

State Key Laboratory of Cognitive Neuroscience and Learning and International Data Group/McGovern Institute for Brain Research, School of Brain and Cognitive Sciences, Beijing Normal University Beijing, China ; Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University Beijing, China.

Studies in rodents revealed that selective accumulation of Na(+) channel subtypes at the axon initial segment (AIS) determines action potential (AP) initiation and backpropagation in cortical pyramidal cells (PCs); however, in human cortex, the molecular identity of Na(+) channels distributed at PC axons, including the AIS and the nodes of Ranvier, remains unclear. We performed immunostaining experiments in human cortical tissues removed surgically to cure brain diseases. We found strong immunosignals of Na(+) channels and two channel subtypes, NaV1.2 and NaV1.6, at the AIS of human cortical PCs. Although both channel subtypes were expressed along the entire AIS, the peak immunosignals of NaV1.2 and NaV1.6 were found at proximal and distal AIS regions, respectively. Surprisingly, in addition to the presence of NaV1.6 at the nodes of Ranvier, NaV1.2 was also found in a subpopulation of nodes in the adult human cortex, different from the absence of NaV1.2 in myelinated axons in rodents. NaV1.1 immunosignals were not detected at either the AIS or the nodes of Ranvier of PCs; however, they were expressed at interneuron axons with different distribution patterns. Further experiments revealed that parvalbumin-positive GABAergic axon cartridges selectively innervated distal AIS regions with relatively high immunosignals of NaV1.6 but not the proximal NaV1.2-enriched compartments, suggesting an important role of axo-axonic cells in regulating AP initiation in human PCs. Together, our results show that both NaV1.2 and NaV1.6 (but not NaV1.1) channel subtypes are expressed at the AIS and the nodes of Ranvier in adult human cortical PCs, suggesting that these channel subtypes control neuronal excitability and signal conduction in PC axons.
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http://dx.doi.org/10.3389/fncel.2014.00297DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4172021PMC
October 2014

Action potential initiation in neocortical inhibitory interneurons.

PLoS Biol 2014 Sep 9;12(9):e1001944. Epub 2014 Sep 9.

State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, School of Brain and Cognitive Sciences, Beijing Normal University, Beijing, China; Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, China.

Action potential (AP) generation in inhibitory interneurons is critical for cortical excitation-inhibition balance and information processing. However, it remains unclear what determines AP initiation in different interneurons. We focused on two predominant interneuron types in neocortex: parvalbumin (PV)- and somatostatin (SST)-expressing neurons. Patch-clamp recording from mouse prefrontal cortical slices showed that axonal but not somatic Na+ channels exhibit different voltage-dependent properties. The minimal activation voltage of axonal channels in SST was substantially higher (∼7 mV) than in PV cells, consistent with differences in AP thresholds. A more mixed distribution of high- and low-threshold channel subtypes at the axon initial segment (AIS) of SST cells may lead to these differences. Surprisingly, NaV1.2 was found accumulated at AIS of SST but not PV cells; reducing NaV1.2-mediated currents in interneurons promoted recurrent network activity. Together, our results reveal the molecular identity of axonal Na+ channels in interneurons and their contribution to AP generation and regulation of network activity.
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http://dx.doi.org/10.1371/journal.pbio.1001944DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4159120PMC
September 2014

Dopaminergic modulation of axonal potassium channels and action potential waveform in pyramidal neurons of prefrontal cortex.

J Physiol 2013 Jul 8;591(13):3233-51. Epub 2013 Apr 8.

Institute of Neuroscience, State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.

Voltage-gated K(+) (KV) channels play critical roles in shaping neuronal signals. KV channels distributed in the perisomatic regions and thick dendrites of cortical pyramidal neurons have been extensively studied. However, the properties and regulation of KV channels distributed in the thin axons remain unknown. In this study, by performing somatic and axonal patch-clamp recordings from layer 5 pyramidal neurons of prefrontal cortical slices, we showed that the rapidly inactivating A-currents mediated the transient K(+) currents evoked by action potential (AP) waveform command (KAP) at the soma, whereas the rapidly activating but slowly inactivating KV1-mediated D-currents dominated the KAP at the axon. In addition, activation of D1-like receptors for dopamine decreased the axonal K(+) currents, as a result of an increase in the activity of cAMP-PKA pathway. In contrast, activation of D2-like receptors showed an opposite effect on the axonal K(+) currents. Further experiments demonstrated that functional D1-like receptors were expressed at the main axon trunk and their activation could broaden the waveforms of axonal APs. Together, these results show that axonal KV channels were subjected to dopamine modulation, and this modulation could regulate the waveforms of propagating APs at the axon, suggesting an important role of dopaminergic modulation of axonal KV channels in regulating neuronal signalling.
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http://dx.doi.org/10.1113/jphysiol.2013.251058DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3717225PMC
July 2013

Enhancement of asynchronous release from fast-spiking interneuron in human and rat epileptic neocortex.

PLoS Biol 2012 8;10(5):e1001324. Epub 2012 May 8.

Institute of Neuroscience, State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.

Down-regulation of GABAergic inhibition may result in the generation of epileptiform activities. Besides spike-triggered synchronous GABA release, changes in asynchronous release (AR) following high-frequency discharges may further regulate epileptiform activities. In brain slices obtained from surgically removed human neocortical tissues of patients with intractable epilepsy and brain tumor, we found that AR occurred at GABAergic output synapses of fast-spiking (FS) neurons and its strength depended on the type of connections, with FS autapses showing the strongest AR. In addition, we found that AR depended on residual Ca²⁺ at presynaptic terminals but was independent of postsynaptic firing. Furthermore, AR at FS autapses was markedly elevated in human epileptic tissue as compared to non-epileptic tissue. In a rat model of epilepsy, we found similar elevation of AR at both FS autapses and synapses onto excitatory neurons. Further experiments and analysis showed that AR elevation in epileptic tissue may result from an increase in action potential amplitude in the FS neurons and elevation of residual Ca²⁺ concentration. Together, these results revealed that GABAergic AR occurred at both human and rat neocortex, and its elevation in epileptic tissue may contribute to the regulation of epileptiform activities.
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http://dx.doi.org/10.1371/journal.pbio.1001324DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3348166PMC
August 2012

Distinct contributions of Na(v)1.6 and Na(v)1.2 in action potential initiation and backpropagation.

Nat Neurosci 2009 Aug 26;12(8):996-1002. Epub 2009 Jul 26.

Institute of Neuroscience, State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.

The distal end of the axon initial segment (AIS) is the preferred site for action potential initiation in cortical pyramidal neurons because of its high Na(+) channel density. However, it is not clear why action potentials are not initiated at the proximal AIS, which has a similarly high Na(+) channel density. We found that low-threshold Na(v)1.6 and high-threshold Na(v)1.2 channels preferentially accumulate at the distal and proximal AIS, respectively, and have distinct functions in action potential initiation and backpropagation. Patch-clamp recording from the axon cut end of pyramidal neurons in the rat prefrontal cortex revealed a high density of Na(+) current and a progressive reduction in the half-activation voltage (up to 14 mV) with increasing distance from the soma at the AIS. Further modeling studies and simultaneous somatic and axonal recordings showed that distal Na(v)1.6 promotes action potential initiation, whereas proximal Na(v)1.2 promotes its backpropagation to the soma.
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http://dx.doi.org/10.1038/nn.2359DOI Listing
August 2009

Neurogenic development of the auditory areas of the midbrain and diencephalon in the Xenopus laevis and evolutionary implications.

Brain Res 2008 Apr 20;1206:44-60. Epub 2008 Feb 20.

Key Laboratory for Cell Proliferation And Regulation Biology, Ministry of Education, Beijing Normal University, China.

To study whether the core-versus-shell pattern of neurogenesis occurred in the mesencephalic and diencephalic auditory areas of amniotes also appears in the amphibian, [(3)H]-thymidine was injected into tadpoles at serial developmental stages of Xenopus laevis. Towards the end of metamorphism, [(3)H]-thymidine labeling was examined and led to two main observations: 1) neuron generation in the principal nucleus (Tp) started at stage 50, and peaked at stage 53, whereas it began at stage 48.5, and peaked around stage 49 in the other two mesencephalic auditory areas, the laminar nucleus (Tl) and the magnocellular nucleus (Tmc). 2) Neuron generation appeared at stage 40, and peaked around stage 52 in the posterior thalamic nucleus (P) and the central thalamic nucleus (C). Our study revealed that, like the cores of mesencephalic auditory nuclei in amniotes, Tp showed differences from Tl and Tmc in the onset and the peak of neurogenesis. However, such differences did not occur in the P and C. Our neurogenetic data were consistent with anatomical and physiological reports indicating a clear distinction between the mesencephalic, but not the diencephalic auditory areas of the amphibian. Our data are helpful to get insights into the organization of auditory nuclei and its evolution in vertebrates.
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http://dx.doi.org/10.1016/j.brainres.2008.01.101DOI Listing
April 2008

[Hypoglycemic effect of saponin from Tribulus terrestris].

Zhong Yao Cai 2002 Jun;25(6):420-2

School of Life Science, East China Normal University, Shanghai 200062.

Objective: To study the hypoglycemic effect of saponin from Tribulus terrestris L.

Method: Alloxan was used to establish the diabetic model in mice. Phenformin Hydrochlride Tables was used as the positive control. The level of glucose, triglyceride, cholesterol and SOD in serum were determined.

Results: The level of serum glucose could be significantly reduced by saponin from Tribulus terrestris, which was the rate of 26.25% and 40.67% in normal mice and diabetic mice in respectively. The level of serum triglyceride could be reduced 23.35%. The saporin could also decrease the content of serum cholesterol. Serum SOD activity of the mice was increased by the saponin.

Conclusion: Saponin from Tribulue terrestris could significantly reduce the level of serum glucose.
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June 2002
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