Publications by authors named "Yao-Hua Li"

24 Publications

  • Page 1 of 1

MRCKβ links Dasm1 to actin rearrangements to promote dendrite development.

J Biol Chem 2021 Apr 29:100730. Epub 2021 Apr 29.

NHC Key Laboratory of Glycoconjugate Research, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China;. Electronic address:

Proper dendrite morphogenesis and synapse formation are essential for neuronal development and function. Dasm1, a member of the immunoglobulin superfamily, is known to promote dendrite outgrowth and excitatory synapse maturation in vitro. However, the in vivo function of Dasm1 in neuronal development and the underlying mechanisms are not well understood. To learn more, Dasm1 knockout mice were constructed and employed to confirm that Dasm1 regulates dendrite arborization and spine formation in vivo. We performed a yeast two-hybrid screen using Dasm1, revealing MRCKβ as a putative partner; additional lines of evidence confirmed this interaction and identified cytoplasmic proline-rich region (823-947 aa) of Dasm1 and MRCKβ self-activated kinase domain (CC1, 410-744 aa) as necessary and sufficient for binding. Using co-immunoprecipitation assay, auto-phosphorylation assay and BS3 cross-linking assay, we show that Dasm1 binding triggers a change in MRCKβ's conformation and subsequent dimerization, resulting in auto-phosphorylation and activation. Activated MRCKβ in turn phosphorylates a class 2 regulatory myosin light chain (MLC2), which leads to enhanced actin rearrangement, causing the dendrite outgrowth and spine formation observed before. Removal of Dasm1 in mice leads to behavioral abnormalities. Together, these results reveal a crucial molecular pathway mediating cell surface and intracellular signaling communication to regulate actin dynamics and neuronal development in the mammalian brain.
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http://dx.doi.org/10.1016/j.jbc.2021.100730DOI Listing
April 2021

Clinical features and prognosis of epilepsy in the elderly in western China.

Seizure 2016 May 7;38:26-31. Epub 2016 Apr 7.

Department of Neurology, West China Hospital, Sichuan University, Chengdu, China. Electronic address:

Purpose: To investigate the characteristics and prognosis of epilepsy amongst older people hospitalized in southwestern China with newly diagnosed epilepsy.

Methods: We prospectively enrolled people older than 65 years who were admitted to a tertiary epilepsy center in West China between January 2008 and January 2013. Participants were divided into early-onset group (those who had a first seizure before age of 65) and late-onset group (those in whom the first seizure occurred after age of 65). Clinical data were collected and all participants were followed for two years.

Results: Of 340 people enrolled, focal seizure (84%) was the most frequent seizure type. Status epilepticus (64.4% vs. 46.7%, p=0.022) and structural epilepsy (59.3% vs. 40.0%, p=0.015) were more prevalent in late-onset group than early-onset group. Ischemic stroke was the leading putative cause (22.6%) in elderly epilepsies. Around 80% were given anti-epileptic drugs (AEDs) for treatment. Forty-two people did not complete the study, of whom 26 were lost to follow-up and 16 died for causes other than epilepsy. Of the 298 who completed the follow-up, 240 (80.5%) achieved significant seizure reduction. Logistic regression analysis indicated that late-onset epilepsies and AEDs treatment were associated with more favorable seizure outcome at two-year follow-up (OR=4.029 and 92.007, respectively). The number of AEDs intake exerted no significant impact on seizure outcome.

Conclusions: In older people, late-onset epilepsies differed in several aspects from early-onset epilepsies. The overall effectiveness of AEDs treatment in older people was satisfactory.
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http://dx.doi.org/10.1016/j.seizure.2016.03.011DOI Listing
May 2016

Effectiveness of levetiracetam use following resective surgery in patients with refractory epilepsy: a prospective observational study.

Epilepsy Res 2014 Dec 13;108(10):1904-11. Epub 2014 Oct 13.

Department of Neurology, West China Hospital of Sichuan University. Electronic address:

Purpose: This study aimed to evaluate the effectiveness of levetiracetam (LEV) use for seizure control in patients who had undergone resective surgery for intractable epilepsy in routine clinical practice.

Methods: This was a prospective, observational study. Refractory epilepsy patients who underwent epilepsy surgery from January 2008 to December 2011 in the Department of Neurosurgery, West China Hospital were prospectively analyzed. Patients were divided into two groups according to antiepileptic drug (AED) treatment used immediately after epilepsy surgery (group A: therapy with LEV; group B: therapy without LEV). AED regimens were compared with regard to seizure-outcome for a period of more than 2 years. The International League Against Epilepsy (ILAE) classification was used to categorize seizure outcome.

Results: A total of 319 patients (184 male and 135 female patients; mean age 28.2±13.4 years) were studied. The mean postoperative follow-up period was 3.9±1.2 years. The two groups showed was no significant difference in preoperative baseline data. At the 6-month follow-up, the proportion of patients with seizure freedom was significantly higher in group A than in group B (78.8% vs. 67.5%, p=0.03). Seizure outcomes after 2 years were assessed using the ILAE classification. The proportion of patients under ILAE seizure-outcome classification I (seizure freedom) was significantly higher in group A than in group B (74.3% vs. 60.7%, p=0.01). Seizure recurrence rates at the final assessment, after planned reduction or withdrawal, were 26.3% for group A and 40.6% for group B (p=0.04).

Conclusions: AED strategy after resective surgery may be a potentially modifiable prognostic indicator influencing seizure outcome in patients with intractable epilepsy. Compared to other AEDs, LEV appears to be more effective in controlling postoperative seizures in our long-term follow-up, and the advantage can be seen in early stage after surgery.
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http://dx.doi.org/10.1016/j.eplepsyres.2014.09.034DOI Listing
December 2014

Nicotine-induced upregulation of VCAM-1, MMP-2, and MMP-9 through the α7-nAChR-JNK pathway in RAW264.7 and MOVAS cells.

Mol Cell Biochem 2015 Jan 9;399(1-2):49-58. Epub 2014 Nov 9.

Department of Cardiology, Shanghai First People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200080, China.

The ability of nicotine to induce aortic aneurysms has been shown in animal models; however, its underlying mechanisms remain elusive. In the present experiment, both the RAW264.7 and MOVAS cell lines were employed to examine the nicotine-induced modulation of VCAM-1, MMP-2, and MMP-9 expressions in macrophages and vascular smooth muscle cells. Our results showed that nicotine concentrations of both 0.5 and 5 ng/ml induced VCAM-1, MMP-2, and MMP-9 upregulation, while a concentration of 50 ng/ml had a slight inhibitory effect and a concentration of 500 ng/ml showed a significant inhibitory effect. When cells were pretreated with either SP600125 (JNK inhibitor) or PNU-282987 (α7-nAChR agonist) prior to nicotine exposure, the nicotine-induced upregulation of VCAM-1, MMP-2, MMP-9, and p-JNK was suppressed, with a joint treatment producing a more significant inhibitory effect. Moreover, PNU-282987 had a comparable inhibitory effect on VCAM-1, MMP-2, and MMP-9 expressions and JNK activation via phosphorylation as did SP600125. In conclusion, nicotine-induced VCAM-1, MMP-2, and MMP-9 expressions occur in a dose-dependent fashion in both of the cell lines tested. Furthermore, the nicotine exposure equivalent to plasma levels found in regular smokers can augment VCAM-1, MMP-2, and MMP-9 expressions through the α7-nAChR-JNK pathway.
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http://dx.doi.org/10.1007/s11010-014-2231-zDOI Listing
January 2015

[Chemical constituents from Embelia laeta].

Zhong Yao Cai 2013 Dec;36(12):1947-9

Objective: To study the chemical constituents from Embelia laeta.

Methods: The constituents from the EtOAc fraction of ethanol extract of Embelia laeta were separated and purified by column chromatography with silica gel and polyamide. The compounds were identified by their physiochemical proerties and spectral data.

Results: Eleven compounds were isolated and identified as p-sitosterol (1), beta-daucosterel (2), gallic acid (3), vanillic acid (4), rutin (5), hyperin (6), quercetin (7), kaemperol ( 8), chrysoeriol (9), physcion(10) and apigenin-7-O-glucoside(ll).

Conclusion: Compounds 5-11 are isolated from this genus for the first time.
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December 2013

Monocyte chemoattractant protein-1 mediates angiotensin II-induced vascular smooth muscle cell proliferation via SAPK/JNK and ERK1/2.

Mol Cell Biochem 2012 Jul 17;366(1-2):355-62. Epub 2012 Apr 17.

Cardiac Vascular Unit, Shanghai First People's Hospital Affiliated to Shanghai Jiao-Tong University, Shanghai 200080, China.

Abnormal vascular smooth muscle cells proliferation is the pathophysiological basis of cardiovascular diseases, such as hypertension, atherosclerosis, and restenosis after angioplasty. Angiotensin II can induce abnormal proliferation of vascular smooth muscle cells, but the molecular mechanisms of this process remain unclear. Here, we explored the role and molecular mechanism of monocyte chemotactic protein-1, which mediated angiotensin II-induced proliferation of rat aortic smooth muscle cells. 1,000 nM angiotensin II could stimulate rat aortic smooth muscle cells' proliferation by angiotensin II type 1 receptor (AT(1)R). Simultaneously, angiotensin II increased monocyte chemotactic protein-1 expression and secretion in a dose-and time-dependent manner through activation of its receptor AT(1)R. Then, monocyte chemotactic protein-1 contributed to angiotensin II-induced cells proliferation by CCR2. Furthermore, we found that intracellular ERK and JNK signaling molecules were implicated in angiotensin II-stimulated monocyte chemotactic protein-1 expression and proliferation mediated by monocyte chemotactic protein-1. These results contribute to a better understanding effect on angiotensin II-induced proliferation of rat smooth muscle cells.
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http://dx.doi.org/10.1007/s11010-012-1315-xDOI Listing
July 2012

Evaluation of different antiepileptic drug strategies in medically refractory epilepsy patients following epilepsy surgery.

Epilepsy Res 2012 Aug 21;101(1-2):14-21. Epub 2012 Mar 21.

Department of Neurology, West China Hospital of Sichuan University, Chengdu, China.

Purpose: This study aimed to explore the most appropriate antiepileptic drug strategies after successful epilepsy surgery.

Methods: A total of 131 refractory epilepsy patients who underwent epilepsy surgery from January 2005 to December 2008 in the Department of Neurosurgery, West China Hospital, were retrospectively reviewed. Patients were divided into three groups (monotherapy, duotherapy, and polytherapy) according to drug combinations used immediately after epilepsy surgery. Seizure outcomes were followed up for more than 2 years. Engel classification was used to evaluate seizure outcomes.

Results: The mean postoperative follow-up period was 3.7±1.0 years. Preoperative baseline data among the three groups were comparable. Seizure recurrence rate in monotherapy was obviously higher than in other groups (34.1% vs. 15.1%, 7.1%) at 6-month follow-up, which showed a statistically significant difference (p=0.02). Seizure outcomes for 2 years were assessed using Engel classification. In the duotherapy group, the rate of Engel class I was definitely higher than in the other two groups (69.9% vs. 47.7%, 57.1%, p=0.02). Seizure relapse rates at the 2-year follow-up, after planned reduction or withdrawal, were 46.4% for monotherapy, 16.9% for duotherapy, and 25.0% for polytherapy (p=0.01).

Conclusions: Monotherapy may be not sufficient enough to control seizures completely. It appears to have a higher risk for seizure relapse when considering drug reduction. It suggests that duotherapy may be more effective and safer than monotherapy. Even after successful epilepsy surgery, duotherapy seems preferable to monotherapy or polytherapy for control of residual seizures.
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http://dx.doi.org/10.1016/j.eplepsyres.2012.02.013DOI Listing
August 2012

Alpha-synuclein functions as a negative regulator for expression of tyrosine hydroxylase.

Acta Neurol Belg 2011 Jun;111(2):130-5

Department of Neurobiology, Ministry of Education, Xuanwu Hospital of China Capital Medical University, Beijing, China.

Previous studies have shown that over-expression of alpha-Synuclein (alpha-Syn), a protein whose abnormality is implicated in the pathogenesis of Parkinson's disease (PD), reduces tyrosine hydroxylase (TH) expression and dopamine synthesis. To explore the possible mechanism for the regulation of TH expression by alpha-Syn, luciferase reporter gene carrying a -493/+27bp fragment of human TH gene (pGL3-TH520) and pcDNA carrying halpha-Syn gene (pcDNA-halpha-Syn) were co-transfected into T293 cells. The results showed that alpha-Syn was only detected in pcDNA-halpha-Syn-transfected cells but not in pcDNA vector control cells. In alpha-Syn-transfected cells, the luciferase activity was dramatically reduced compared with the vector control cells. These results suggest that alpha-Syn may function as a negative regulator for TH expression by affecting the activity of TH promoter.
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June 2011

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry combined with magnetic beads for detecting serum protein biomarkers in parkinson's disease.

Eur Neurol 2011 27;65(2):105-11. Epub 2011 Jan 27.

Beijing Institute of Geriatrics, Xuanwu Hospital of Capital University of Medical Sciences, Key Laboratory for Neurodegenerative Diseases of Ministry of Education, Beijing, China.

Background: Biomarkers for neurodegenerative diseases are essential to facilitate disease diagnosis. Application of proteomics has greatly hastened the search for novel biomarkers. In this study, new potential biomarkers were discovered, and a diagnostic pattern was established for idiopathic Parkinson's disease (PD) by using proteomic technology.

Methods: Serum proteins from PD patients and controls were captured by magnetic bead-based weak cation exchange. The molecular weight of the proteins in bead-binding fraction was detected by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Biomarker Wizard 3.1 and Biomarker Patterns Software were used for data analysis and constructing a model of biomarkers. A blinded testing set was used to validate the model.

Results: A total of 17 discriminating m/z peaks related to PD were identified. The model based on the 5 biomarkers generated an excellent separation between PD and healthy controls with 98.36% for the sensitivity and 83.05% for the specificity. Blind test data demonstrated the model could recognize patients with PD with a sensitivity of 85.0% and a specificity of 70.0%.

Conclusions: The preliminary data suggested a potential application of MALDI-TOF-MS combined with magnetic beads. The model comprising 5 promising biomarkers can differentiate individuals with PD and the healthy subjects precisely.
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http://dx.doi.org/10.1159/000323427DOI Listing
June 2011

[Remote passive sensing of aeroengine exhausts using FTIR system].

Guang Pu Xue Yu Guang Pu Fen Xi 2009 Mar;29(3):616-9

Civil Aviation College, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.

The traditional method of measuring the aeroengine exhausts is intrusive gas sampling analysis techniques. The disadvantages of the techniques include complex system, difficult operation, high costs and potential danger because of back-pressure effects. The non-intrusive methods have the potential to overcome these problems. So the remote FTIR passive sensing is applied to monitor aeroengine exhausts and determine the concentration of the exhausts gases of aeroengines. The principle of FTIR remote passive sensing is discussed. The model algorithm for the calibration of FTIR system, the radiance power distribution and gas concentration are introduced. TENSOR27 FTIR-system was used to measure the spectra of infrared radiation emitted by the hot gases of exhausts in a test rig. The emission spectra of exhausts were obtained under different thrusts. By analyzing the spectra, the concentrations of CO2, CO and NO concentration were calculated under 4 thrusts. Researches on the determination of concentration of the exhausts gases of aeroengines by using the remote FTIR sensing are still in early stage in the domestic aeronautics field. The results of the spectra and concentration in the aeroengine test are published for the first time. It is shown that the remote FTIR passive sensing techniques have a great future in monitoring the hot gas of the aeroengines exhausts.
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March 2009

Upregulation of Ryk expression in rat dorsal root ganglia after peripheral nerve injury.

Brain Res Bull 2008 Oct 4;77(4):178-84. Epub 2008 Sep 4.

State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, 15 Da-tun Road, Beijing 100101, China.

To study changes of Ryk expression in dorsal root ganglia (DRG) after peripheral nerve injury, we set up an animal model of unilateral sciatic nerve lesioned rats. Changes of Ryk protein expression in DRG neurons after unilateral sciatic nerve injury were investigated by immunostaining. Changes of Ryk mRNA were also tested by semi-quantitative PCR concurrently. We found, both at the level of protein and mRNA, that Ryk could be induced in cells of ipsilateral DRG after unilateral sciatic nerve lesion. Further investigation by co-immunostaining confirmed that the Ryk-immunoreactive (Ryk-IR) cells were NeuN-immunoreactive (NeuN-IR) neurons of DRG. We also showed the pattern of Ryk induction in DRG neurons after sciatic nerve injury: the number of Ryk IR neurons peaked at 2 weeks post-lesion and decreased gradually by 3 weeks post-lesion. The proportions of different sized Ryk IR neurons were also observed and counted at various stages after nerve lesion. Analysis of Ryk mRNA by RT-PCR showed the same induction pattern as by immunostaining. Ryk mRNA was not expressed in normal or contralateral DRG, but was expressed 1, 2 and 3 weeks post-lesion in the ipsilateral DRG. Ryk mRNA levels increased slightly from 1 to 2 weeks, decreased then by 3 weeks post-lesion. These results indicate that Ryk might be involved in peripheral nerve plasticity after injury. This is a novel function apart from its well-known fundamental activity as a receptor mediating axon guidance and outgrowth.
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http://dx.doi.org/10.1016/j.brainresbull.2008.05.011DOI Listing
October 2008

[Aberrant immunophenotypes in 126 patients with acute leukemia].

Zhongguo Shi Yan Xue Ye Xue Za Zhi 2007 Oct;15(5):1032-6

Department of Hematology, Xuanwu Hospital of Capital University of Medical Sciences, Beijing 100053, China.

The existence of leukemia aberrant immunophenotypes (LAIP) has been suggested to be a valuable tool for the detection of minimal residual disease (MRD), as they could distinguish leukemic cells from normal hematopoietic progenitors. This study was purposed to analyze the characteristics of LAIP in acute leukemia and further explore the proportion of different types of LAIP in acute leukemia patients. Flow cytometry (FCM) with four color and CD45/SSC gating were used to detect the antigen expression in samples of bone marrow from 126 patients with acute leukemia. The results showed that definite LAIP could be detected in about 76% patients. The LAIP could be divided into four groups as cross-lineage antigen expression, asynchronous antigen expression, antigen overexpression and antigen lack expression. The percentages of these LAIPs were 39%, 46%, 21% and 29% respectively. About 11% out of analyzed cases showed the existence of only one aberrant phenotype while two or more of aberrant phenotypes could be detected in majority cases. It is concluded that the LAIP with four subgroups can be detected in the majority of patients with acute leukemia and immunophenotyping based on LAIP is applicable for the detection of MRD.
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October 2007

cDNA cloning, prokaryotic expression and purification of rat alpha-synuclein.

Neurosci Bull 2006 Jan;22(1):29-33

Department of Neurobiology, Beijing Institute of Geriatrics, Xuanwu Hospital of Capital University of Medical Sciences, Beijing 100053, China E-mail: [email protected] yahoo.com.cn.

Objective To clone the cDNA of rat alpha-Syn gene, investigate its prokaryotic expression and produce purified recombinant rat alpha-Syn protein. Methods Rat alpha-Syn cDNA was amplified from the rat brain total RNA by RT-PCR and was cloned into pGEX-4T-1, a prokaryotie expressing vector. The recombinant plasmid containing rat alpha-Syn gene was transformed into E. Coli BL21 to express a fusion protein with rat alpha-Syn protein tagged by glutathione-S-transferase (GST). The fusion protein was then cleaved by thrombin during passing through the GST-agarose 4B column to release the recombinant rat alpha-Syn protein. The recombinant rat alpha-Syn protein was further purified using Superdex S200 gel filtration.Results DNA sequencing confirmed that the cloned cDNA contained 420 base pairs encoding 140 amino acids, which was identical to the reported amino acid sequence of rat alpha-Syn. After transformation, the recombinant plasmid pGEX-raSyn expressed a soluble protein that was inducible by IPTG. The purified recombinant protein was shown to be single band on SDS-PAGE, with a molecular size of around 18000, which was identical to the reported molecular size of rat alpha-Syn.Western blot analysis demonstrated that the recombinant protein was recognized by specific antibody against alpha-Syn. Conclusion The rat alpha-Syn gene was successfully expressed in prokaryotic expression system and highly purified rat alpha-Syn recombinant protein was produced.
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January 2006

Effect of alpha-synuclein on the promoter activity of tyrosine hydroxylase gene.

Neurosci Bull 2007 Jan;23(1):53-7

Department of Neurobiology, Beijing Institute of Geriatrics, Xuanwu Hospital of Capital University of Medical Sciences, Beijing 100053, China.

Objective: To approach the associated mechanism by which alpha-synuclein (alpha-Syn) might regulate the metabolism of dopamine.

Methods: A DNA fragment, located at -495 to +25 of the human tyrosine hydroxylase (TH) gene, was amplified by PCR and inserted into the pGL(3)-Basic luciferase reporter vector. The recombinant plasmid pGL(3)-THprom was transfected into a dopaminergic cell line MES23.5 or a alpha-Syn over-expressed MES23.5 (named MES23.5/halpha-Syn(+)). The promoter activity was detected by the Dual Luciferase Assay System.

Results: The luciferase activities in the MES23.5 cells transfected with pGL(3)-Basic, pGL(3)-THprom, and pGL(3)-Control vectors were 5.60+/-0.67, 26.80+/-4.11, and 32.90+/-4.75, respectively. On the other hand, the luciferase activity of pGL(3)-THprom in the MES23.5 (26.80+/-4.11) was significantly higher than that in the MES23.5/halpha-Syn(+) (14.40+/-0.61) (P<0.01).

Conclusion: These results indicate that the - 495 to +25 region in the TH gene possesses promoter activity for controlling the gene expression, and that alpha-Syn may negatively regulate the metabolism of dopamine by affecting the function of TH promoter as a trans-acting factor.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5550569PMC
http://dx.doi.org/10.1007/s12264-007-0008-zDOI Listing
January 2007

Repetition rates of specific interval patterns in single spike train reflect excitation level of specific receptor types, shown by high-speed favored-pattern detection method.

Brain Res 2006 Oct 23;1113(1):110-28. Epub 2006 Aug 23.

Department of Physiology, Peking University Health Science Center, Beijing 100083, PR China.

Unlabelled: Interval patterns in single spike train, e.g. "favored patterns (FPs, the FP is a sequence of successive intervals of action potentials that occur more often than what is reasonably expected at random.)", may represent neural codes containing information. The present study developed a "high-speed FP-detection method" which could qualitatively and quantitatively analyze FPs. By using this method, single spike trains of nucleus paraventricularis (NPV) and rostral ventrolateral medulla (RVL) having different firing patterns, being involved in regulation of arterial pressure, and controlled by different transmitters, were chosen for analysis.

Results: (1) Corticotropin releasing factor, substance P and agonists of alpha-, beta- and M-receptor microinjected into these brain areas, respectively, induced dominant change of specific FP. Repetition rates of specific FPs reflect excitation level of specific receptor types. It shows that chemical codes (different transmitters with their receptor types or subtypes) are transformed into electrical codes (different FPs). (2) When alpha-, beta- and M-receptors of RVL neurons were activated simultaneously by intrinsic excitatory transmitters released due to activation of input pathway, only repetition rate of the specific FP that represented the predominant activity of the receptor type (alpha-adrenergic receptor) markedly increased. The activities of other receptor types (beta- and M-receptors) were masked. (3) Intrinsic inhibitory transmitters (GABA, beta-endorphin) in the RVL all decreased specific FP repetition rate of dominant receptor type. These results may provide a new way to further explore how information in the CNS is conveyed and processed.
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http://dx.doi.org/10.1016/j.brainres.2006.06.119DOI Listing
October 2006

[Study on quality analysis of essential oil from twig and leaf of Baeckea frutescens].

Zhongguo Zhong Yao Za Zhi 2004 Jun;29(6):539-42

Guangxi Institute of traditional Medical and Pharmaceutical Sciences, Nanning 530022, China.

Objective: To provide scientific methods for quality criterion by studying the chemical components of essential oil from Baeckea frutescens.

Method: The chemical components of essential oil from B. frutescens were identified by GC-MS-DS, TLC and capillary GC. The relative contents of main components were determined by area normalization.

Result: More than 50 peaks were separated, and 38 components were identified, which accounted for over 94% of the total GC peaks areas of the essential oil. The methods for quality evaluation of essential oil from B. frutescens by TLC and capillary GC were established.

Conclusion: The chemical components of essential oil from B. frutescens collected from different habitats and collecting periods have common characteristics as well as differences. Some components, such as linalool, can be used as a standard and chromatography fingerprint to analyze the quality of essential oil from B. frutescens.
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June 2004

Inhibitory effect of atriopeptinergic neurons in AV3V region on angiotensinII pressor system in rat brain.

Peptides 2004 Apr;25(4):615-20

Department of Physiology, Peking University Health Science Center, Beijing 100083, PR China.

In the central nervous system and the periphery, atrial natriuretic peptide (ANP) and angiotensinII(AngII) play important and opposite roles in regulating blood pressure and fluid electrolyte balance. Their central mechanisms are unclear. In the brain the anteroventral third ventricle region (AV3V) contains the most prominent collection of atriopeptin-like immunoreactive perikarya. Our previous studies show that: (1) AV3V stimulation by glutamate produces a fall in blood pressure; (2) there is an AngII pressor system composed of the lateral hypothalamus/perifornical region (LH/PF), subfornical organ (SFO), nucleus paraventricularis (NPV) and rostral ventrolateral medulla (RVL). The present study was to examine whether ANPergic projections from the AV3V could act on nuclei involved in the above-mentioned AngII pressor system. Here we demonstrate that: (1) Injection of atriopeptinIII into the LH/PF, SFO, NPV, or RVL induces a depressor response; whereas injection of normal saline has no effect. (2) Pre-injection of A 71915 (an atriopeptinIII antagonist) into the LH/PF, SFO, NPV, or RVL reverses the depressor response of the AV3V to glutamate (Glu). The results suggest that excitation of atriopeptinergic neurons in the AV3V by Glu produces an inhibitory effect on each nucleus in the LH/PF-SFO-NPV-RVL AngII pressor system.
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http://dx.doi.org/10.1016/j.peptides.2004.02.021DOI Listing
April 2004

[Effect of repeated acute hypoxic treatment on the expression of alpha-synuclein in the mouse brain cortex].

Sheng Li Xue Bao 2004 Apr;56(2):263-8

Department of Neurobiology, Beijing Institute of Geriatrics, Xuan Wu Hospital, Capital University of Medical Sciences.

An anti-alpha-synuclein (alpha-SYN) monoclonal antibody produced in our laboratory was used to investigate the effect of repeated acute hypoxic treatments on the expression of alpha-SYN in the mouse cerebral cortex. Western blot analysis showed that the expression levels of alpha-SYN in the cortex changed accordingly upon hypoxic exposure times, as that the alpha-synuclein level significantly increased after the first hypoxic exposure and then dropped down to the background level after the fourth hypoxic exposure. Immunohistochemical staining revealed that the alpha-SYN-immunopositive substance was localized not only in the nerve endings, but also within the nuclei of some neurons. The cell density of the neurons with alpha-SYN immunopositive nuclei was increased significantly after the first hypoxic exposure but returned back to control levels after the fourth hypoxic exposure. Our results indicate that both of the alpha-SYN expression level in the brain and the number of the neurons with alpha-SYN positive nuclei are affected by the repeated acute hypoxic treatments and that this modification is hypoxic time-dependent. The mechanism and the physiological significance underlying these changes need to be further investigated.
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April 2004

Subfornical organ-angiotensin II pressor system takes part in pressor response of emotional circuit.

Peptides 2003 Jul;24(7):1063-7

Department of Physiology, Peking University Health Science Center, Beijing 100083, PR China.

It has been proved that there are the subfornical organ (SFO)-nucleus paraventricularis (NPV)-rostral ventrolateral medulla (RVL) angiotension II (AngII) pressor system and the central amygdaloid nucleus (AC)-lateral hypothalamus/perifornical region (LH/PF) emotional pressor system in the brain. Because the LH/PF contains abundant AngII ergic neurons projecting to the SFO, the purpose of the present study was to examine whether the (SFO-NPV-RVL) AngII pressor system takes part in the AC-pressor response via AngII ergic neurons in the LH/PF. The results showed that (1) L-glutamate microinjection into the AC or LH/PF induced pressor responses. (2) Both the AC- and LH/PF-pressor responses could be reversed by preinjection of [Sar(1), Thr(8)]-angiotensin II (an antagonist of AngII) into either the SFO, NPV or RVL. Taken together with our previous findings that the projections of the CRF-ergic and SP-ergic neurons in the AC could activate the LH/PF, the above findings prove that: besides several known mechanisms of the brain AngII inducing pressor response, the (SFO-NPV-RVL) AngII pressor system also takes part in the AC-emotional pressor response via AngII ergic projections from the LH/PF to the SFO, which may be the neurophysiological basis of the brain AngII playing an important role in developing hypertension of the SHRs.
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http://dx.doi.org/10.1016/s0196-9781(03)00180-3DOI Listing
July 2003

Inhibition of recombinant dipeptidyl peptidase III by synthetic hemorphin-like peptides.

Peptides 2003 May;24(5):773-8

Department of Orthopaedics, Nagoya City University Medical School, Mizuho-ku, 467-8601 Nagoya, Japan.

In order to find the most effective antagonist for dipeptidyl peptidase III degrading enkephalin, we synthesized hemorphin-like pentapeptides with aliphatic or aromatic amino acids at the N-termini, such as VVYPW, LVYPW, IVYPW, YVYPW, FVYPW and WVYPW. Among those pentapeptides, IVYPW and WVYPW showed the strongest inhibitory activity toward rDPP III. The K(i) values of IVYPW and WVYPW were 0.100+/-0.011 and 0.126+/-0.015 microM (mean+/-S.E.), respectively. The order of K(i) values was Ile> or =Trp>Phe> or =Tyr>Leu>Ala>Val>Ser>Gly. rDPP III activity is inhibited in a non-competitive manner by these peptides. The peptide VYPW did not inhibit rDPP III activity, but the sequence is essential for the expression of inhibitory activity.
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http://dx.doi.org/10.1016/s0196-9781(03)00119-0DOI Listing
May 2003

An A-71C substitution in a green gene at the second position in the red/green visual-pigment gene array is associated with deutan color-vision deficiency.

Proc Natl Acad Sci U S A 2003 Mar 7;100(6):3357-62. Epub 2003 Mar 7.

Departments of Medical Biochemistry and Ophthalmology, Shiga University of Medical Science, Seta, Otsu 520-2192, Japan.

We studied 247 Japanese males with congenital deutan color-vision deficiency and found that 37 subjects (15.0%) had a normal genotype of a single red gene followed by a green gene(s). Two of them had missense mutations in the green gene(s), but the other 35 subjects had no mutations in either the exons or their flanking introns. However, 32 of the 35 subjects, including all 8 subjects with pigment-color defect, a special category of deuteranomaly, had a nucleotide substitution, A-71C, in the promoter of a green gene at the second position in the red/green visual-pigment gene array. Although the -71C substitution was also present in color-normal Japanese males at a frequency of 24.3%, it was never at the second position but always found further downstream. The substitution was found in 19.4% of Chinese males and 7.7% of Thai males but rarely in Caucasians or African Americans. These results suggest that the A-71C substitution in the green gene at the second position is closely associated with deutan color-vision deficiency. In Japanese and presumably other Asian populations further downstream genes with -71C comprise a reservoir of the visual-pigment genes that cause deutan color-vision deficiency by unequal crossing over between the intergenic regions.
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http://dx.doi.org/10.1073/pnas.0637437100DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC152297PMC
March 2003

Legumain from bovine kidney: its purification, molecular cloning, immunohistochemical localization and degradation of annexin II and vitamin D-binding protein.

Biochim Biophys Acta 2002 Apr;1596(1):108-20

Department of Medical Biochemistry, Shiga University of Medical Science, Seta, Otsu 520-2192, Japan.

Legumain (asparaginyl endopeptidase) was purified to homogeneity from bovine kidneys. The molecular mass of the purified enzyme was calculated to be 34000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the presence of beta-mercaptoethanol. The enzyme rapidly hydrolyzed the substrate Z-Ala-Ala-Asn-MCA and was strongly inhibited by N-ethylmaleimide, p-chloromercuribenzene-sulfonic acid, Hg(2+) and Cu(2+). The amino acid sequence of the first 26 residues of the enzyme was Gly-Gly-Lys-His-Trp-Val-Val-Ile-Val-Ala-Gly-Ser-Asn-Gly-Gln-Tyr-Asn-Tyr-Arg-His-Gln-Ala-Phe-Ala-Asp-His-. This sequence is highly homologous to the sequences in the N-terminal of pig kidney legumain. We screened a bovine kidney cortex cDNA library using a DNA probe that originated from rat legumain, and we determined the bovine kidney cDNA structure and deduced the amino acid sequence. The cDNA is composed 1934 bp and encodes 433 amino acids in the coding region. The enzyme was strongly stained in the proximal tubules of the rat kidney in an immunohistochemical study. Vitamin D-binding protein which is known to be a ligand to megalin existing in the proximal tubules, was cleaved in a limited proteolytic manner by bovine kidney legumain. These results suggested that legumain contributes to the processing of macromolecules absorbed by proximal tubule cells. The enzyme also cleaved an N-terminal synthetic peptide of bovine annexin II (Gly(24)-Ser-Val-Lys-Ala-Tyr-Thr(30)-Asn-Phe-Asp-Ala-Glu(35)-Arg-Asp(37)) at a position between Asn(31) and Phe(32). The amino-terminal domain of annexin II has p11 subunit binding sites and phosphorylation sites for both pp60(src) and protein kinase C. This suggests that legumain plays an important role in inactivation and degradation of annexin II, which is abundant in the receptor-recycling compartments of endosomes/lysosomes.
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http://dx.doi.org/10.1016/s0167-4838(02)00209-1DOI Listing
April 2002

Involvement of rat lateral septum-acetylcholine pressor system in central amygdaloid nucleus-emotional pressor circuit.

Neurosci Lett 2002 Apr;323(1):60-4

Department of Physiology and Pathophysiology, Health Science Center, Peking University, 100083, Beijing, People's Republic of China.

There is an emotional pressor circuit composed of nuclei controlling emotion and stress, which may be the neurophysiological basis for prolonged emotional stress inducing hypertension. The central amygdaloid nucleus (AC) is the most important in this circuit, which widely connects with the other nuclei via its CRF (corticotropin releasing factor)-ergic and SP (substance P)-ergic projection fibers. There is another pressor system composed of the lateral septum (SL), habenula (HB), locus coeruleus (LC), and rostral ventrolateral medulla (RVL); muscarinic receptors are involved in each connection of this system. In view of the facts that the SL also plays an important role in integration of emotion and autonomic reaction, and the AC projects to the SL, it is likely that the SL-acetylcholine (ACh) pressor system is involved in the AC-emotional circuit. The present study demonstrates that injection of receptor blocker into each nucleus in the SL-ACh pressor pathway can reverse the AC pressor response, proving that the SL-HB (and HB-posterior hypothalamus)-LC-RVL pressor system is a component of the AC-emotional pressor circuit.
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http://dx.doi.org/10.1016/s0304-3940(01)02531-9DOI Listing
April 2002