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ABSTRACT: Immunoglobulin superfamily (IgSF) molecules are actively involved in cell-cell adhesion, neuronal migration, axonal guidance and synapse formation in the nervous system. Kirre, as a member of this family, has been implicated in mammalian neuronal differentiation and development. Although the distribution of rKirre (a rat homologue of Drosophila Kirre) mRNA was previously analyzed in adult rat cerebellum by in situ hybridization, the expression levels of transcript and protein were not well studied. Here, we showed that the expressions of rKirre mRNA and protein significantly increased during postnatal development of rat cerebellum. rKirre mRNA was mainly expressed in the granular layers and Purkinje cell layer in the developing cerebellum, revealing a possible involvement of rKirre in granule cell migration and Purkinje cell development. An essential relationship between rKirre and Purkinje cells was implied by the co-localization of rKirre and NF-200 on the cell bodies of Purkinje cells. These results suggest that rKirre may play a potential role in postnatal developing rat cerebellum.
Neuroscience Letters 04/2013; · 2.11 Impact Factor
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ABSTRACT: Roots of (Danggui) have been used in promoting blood circulation as herbal medicine for over 2000 years in China. Another species of roots called is being used in Korea. To reveal the efficiency of different roots, the chemical and biological properties of roots from different cultivated regions were compared. Roots of contained higher levels of ferulic acid, Z-ligustilide, and senkyunolide A, while high amounts of butylphthalide and Z-butylenephthalide were found in roots. The extracts deriving from roots showed better effects in osteogenic and estrogenic properties than that of from China. However, this difference was markedly reduced when the roots were being prepared in a Chinese herbal decoction together with Astragali Radix as Danggui Buxue Tang. In contrast, the herbal decoction prepared from roots showed better responses in cell cultures. In addition, the extracts of roots showed strong cell toxicity both as single herb and as Danggui Buxue Tang. This result revealed the distinct properties of roots from China and Korea suggesting the specific usage of herb in preparing a unique herbal decoction.
Evidence-based Complementary and Alternative Medicine 01/2013; 2013:483286. · 4.77 Impact Factor
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ABSTRACT: The gene encoding the collagen-tailed subunit (ColQ) of acetylcholinesterase (AChE) contains two distinct promoters that drive the production of two ColQ mRNAs, ColQ-1 and ColQ-1a, in slow- and fast-twitch muscles, respectively. ColQ-1a is expressed at the neuromuscular junction (NMJ) in fast-twitch muscle, and this expression depends on trophic factors supplied by motor neurons signaling via a cAMP-dependent pathway in muscle. To further elucidate the molecular basis of ColQ-1a's synaptic expression, here we investigated the expression and localization of cAMP-responsive element binding protein (CREB) at the synaptic and extra-synaptic regions of fast- and slow-twitch muscles from adult rats. The total amount of active, phosphorylated CREB (P-CREB) present in slow-twitch soleus muscle was higher than that in fast-twitch tibialis muscle, but P-CREB was predominantly expressed in the fast-twitch muscle at NMJs. In contrast, P-CREB was detected in both synaptic and extra-synaptic regions of slow-twitch muscle. These results reveal, for the first time, the differential distribution of P-CREB in fast- and slow-twitch muscles, which might support the crucial role of cAMP-dependent signaling in controlling the synapse-specific expression of ColQ-1a in fast-twitch muscles.
Chemico-biological interactions 11/2012; · 2.46 Impact Factor
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ABSTRACT: Acetylcholinesterase (AChE) is well-known for its cholinergic functions in the nervous system; however, this enzyme is also found in other tissues where its function is still not understood. AChE is synthesized through alternative splicing as splicing variants, with isoforms including read-through (AChE(R)), tailed (AChE(T)) and hydrophobic (AChE(H)). In human erythrocytes, AChE(H) is a glycophosphatidylinositol-linked dimer on the plasma membrane. Three N-linked glycosylation sites have been identified in the catalytic domain of human AChE. Here, we investigate the roles of glycosylation in assembly and trafficking of human AChE(H). In transfected fibroblasts, expression of AChE(H) was able to mimic the function of the dimeric form of AChE on the erythrocyte membrane. A glycan-depleted form was constructed by site-directed mutagenesis. By comparison with the wild-type AChE(H), the mutant had a much lower enzymatic activity and a much higher K(m) value. In addition, the mutant was dimerized in the endoplasmic reticulum, but was not trafficked to the Golgi apparatus. The results suggest that the glycosylation may affect AChE(H) enzymatic activity and trafficking, but not dimer formation. The present findings indicate the significance of N-glycosylation in controlling the biosynthesis of the AChE(H) dimer form.
FEBS Journal 07/2012; 279(17):3229-39. · 3.79 Impact Factor
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ABSTRACT: Acetylcholinesterase (AChE) is organized into globular tetramers (G(4)) by a structural protein called proline-rich membrane anchor (PRiMA), anchoring it into the cell membrane of neurons in the brain. The assembly of AChE tetramers with PRiMA requires the presence of a C-terminal "t-peptide" in the AChE catalytic subunit (AChE(T)). The glycosylation of AChE(T) is known to be required for its proper assembly and trafficking; however, the role of PRiMA glycosylation in the oligomer assembly has not been revealed. PRiMA is a glycoprotein containing two putative N-linked glycosylation sites. By using site-directed mutagenesis, the asparagine-43 was identified to be the N-linked glycosylation site of PRiMA. Abolishing glycosylation on mouse PRiMA appeared not to affect its assembly with AChE(T), the enzymatic properties of AChE, and the membrane trafficking of PRiMA-linked AChE tetramers. This result is contrary to the reports that glycosylation is essential for conformation and trafficking of membrane glycoproteins.
Neuroscience Letters 06/2012; 523(1):71-5. · 2.11 Impact Factor
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Karl W. K. Tsim,
K. Wing Leung,
Ka Wai Mok,
Vicky P. Chen,
Kevin Y. Zhu,
Judy T. T. Zhu,
Ava J. Y. Guo,
Cathy W. C. Bi,
Ken Y. Z. Zheng,
David T. W. Lau,
Heidi Q. Xie, Roy C. Y. Choi
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ABSTRACT: Acetylcholinesterase (AChE) is well known to process different molecular forms via the distinct interacting partners. Proline-rich
membrane anchor (PRiMA)-linked tetrameric globular AChE (G4 AChE) is mainly found in the vertebrate brain; however, recent
studies from our laboratory have suggested its existence at neuromuscular junctions (nmjs). Both muscle and motor neuron express
AChE at the nmjs. In muscle, the expression of PRiMA-linked AChE is down-regulated during myogenic differentiation and by
motor neuron innervation. As compared with muscle, spinal cord possessed higher total AChE activity and contained PRiMA-linked
AChE forms. The spinal cord expression of this form increased during development. More importantly, PRiMA-linked G4 AChE identified
as aggregates localized at nmjs. These findings suggest that the restricted localization of PRiMA-linked G4 AChE at the nmjs
could be contributed by the pre-synaptic motor neuron and/or the post-synaptic muscle fiber.
Journal of Molecular Neuroscience 04/2012; 40(1):40-46. · 2.50 Impact Factor
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ABSTRACT: A microfluidic chip based nano-HPLC coupled to tandem mass spectrometry (nano-HPLC-Chip-MS/MS) has been developed for simultaneous measurement of abused drugs and metabolites: cocaine, benzoylecgonine, cocaethylene, norcocaine, morphine, codeine, 6-acetylmorphine, phencyclidine, amphetamine, methamphetamine, MDMA, MDA, MDEA, and methadone in the hair of drug abusers. The microfluidic chip was fabricated by laminating polyimide films and it integrated an enrichment column, an analytical column and a nanospray tip. Drugs were extracted from hairs by sonication, and the chromatographic separation was achieved in 15 min. The drug identification and quantification criteria were fulfilled by the triple quardropule tandem mass spectrometry. The linear regression analysis was calibrated by deuterated internal standards with all of the R(2) at least over 0.993. The limit of detection (LOD) and the limit of quantification (LOQ) were from 0.1 to 0.75 and 0.2 to 1.25 pg/mg, respectively. The validation parameters including selectivity, accuracy, precision, stability, and matrix effect were also evaluated here. In conclusion, the developed sample preparation method coupled with the nano-HPLC-Chip-MS/MS method was able to reveal the presence of drugs in hairs from the drug abusers, with the enhanced sensitivity, compared with the conventional HPLC-MS/MS.
Analytical and Bioanalytical Chemistry 03/2012; 402(9):2805-15. · 3.78 Impact Factor
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Cathy W C Bi,
Li Xu,
Xiao Yu Tian,
Jian Liu,
Ken Y Z Zheng,
Chi Wai Lau,
David T W Lau, Roy C Y Choi,
Tina T X Dong,
Yu Huang,
Karl W K Tsim
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ABSTRACT: Fo Shou San (FSS) is an ancient herbal decoction comprised of Chuanxiong Rhizoma (CR; Chuanxiong) and Angelicae Sinensis Radix (ASR; Danggui) in a ratio of 2∶3. Previous studies indicate that FSS promotes blood circulation and dissipates blood stasis, thus which is being used widely to treat vascular diseases. Here, we aim to determine the cellular mechanism for the vascular benefit of FSS. The treatment of FSS reversed homocysteine-induced impairment of acetylcholine (ACh)-evoked endothelium-dependent relaxation in aortic rings, isolated from rats. Like radical oxygen species (ROS) scavenger tempol, FSS attenuated homocysteine-stimulated ROS generation in cultured human umbilical vein endothelial cells (HUVECs), and it also stimulated the production of nitric oxide (NO) as measured by fluorescence dye and biochemical assay. In addition, the phosphorylation levels of both Akt kinase and endothelial NO synthases (eNOS) were markedly increased by FSS treatment, which was abolished by an Akt inhibitor triciribine. Likewise, triciribine reversed FSS-induced NO production in HUVECs. Finally, FSS elevated intracellular Ca(2+) levels in HUVECs, and the Ca(2+) chelator BAPTA-AM inhibited the FSS-stimulated eNOS phosphorylation. The present results show that this ancient herbal decoction benefits endothelial function through increased activity of Akt kinase and eNOS; this effect is causally via a rise of intracellular Ca(2+) and a reduction of ROS.
PLoS ONE 01/2012; 7(12):e51670. · 4.09 Impact Factor
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ABSTRACT: Flavonoids, a group of compounds mainly derived from vegetables and herbal medicines, share a chemical resemblance to estrogen, and indeed some of which have been used as estrogen substitutes. In searching for possible functions of flavonoids, the neuroprotective effect in brain could lead to novel treatment, or prevention, for neurodegenerative diseases. Here, different subclasses of flavonoids were analyzed for its inductive role in neurite outgrowth of cultured PC12 cells. Amongst the tested flavonoids, a flavonol aglycone, isorhamnetin that was isolated mainly from the leaves of Ginkgo biloba L. showed robust induction in the expression of neurofilament, a protein marker for neurite outgrowth, of cultured PC12 cells. Although isorhamnetin by itself did not show significant inductive effect on neurite outgrowth of cultured PC12 cells, the application of isorhamnetin potentiated the nerve growth factor- (NGF-)induced neurite outgrowth. In parallel, the expression of neurofilaments was markedly increased in the cotreatment of NGF and isorhamnetin in the cultures. The identification of these neurite-promoting flavonoids could be very useful in finding potential drugs, or food supplements, for treating various neurodegenerative diseases, including Alzheimer's disease and depression.
Evidence-based Complementary and Alternative Medicine 01/2012; 2012:278273. · 4.77 Impact Factor
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Cathy W C Bi,
Li Xu,
Wendy L Zhang,
Janis Y X Zhan,
Qiang Fu,
Ken Y Z Zheng,
Vicky P Chen,
David T W Lau, Roy C Y Choi,
Tie J Wang,
Tina T X Dong,
Karl W K Tsim
[show abstract]
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ABSTRACT: Fo Shou San (FSS) is an ancient herbal decoction composed of Angelicae Sinensis Radix (ASR; Danggui) and Chuanxiong Rhizoma (CR; Chuanxiong) in a ratio of 3:2. FSS is mainly prescribed for patients having a deficiency of blood supply, and it indeed has been shown to stimulate the production of erythropoietin (EPO) in cultured cells. In order to reveal the mechanism of this FSS-induced EPO gene expression, the upstream regulatory cascade, via hypoxia-induced signaling, was revealed here in cultured hepatocellular carcinoma cell line Hep3B. The induction of EPO gene expression, triggered by FSS, was revealed in cultured hepatocytes by: (i) the increase of EPO mRNA; and (ii) the activation of the hypoxia response element (HRE), an upstream regulator of the EPO gene. The FSS-induced EPO gene expression was triggered by an increased expression of hypoxia-inducible factor-1 α (HIF-1 α) protein; however, the mRNA expression of HIF-1 α was not altered by the treatment of FSS. The increased HIF-1 α was a result of reduced protein degradation after the FSS treatment. The current results therefore provide one of the molecular mechanisms of this ancient herbal decoction for its hematopoietic function.
Planta Medica 11/2011; 78(2):122-7. · 2.15 Impact Factor
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ABSTRACT: ETHNOPHARMACOLOGICAL EVIDENCE: Numerous efforts have been conducted in searching for effective agents against cardiovascular diseases, in particular from herbal medicines. The rhizome of Dioscorea nipponica (Dioscoreae Nipponicae Rhizoma) is a traditional Chinese herb being prescribed to improve the blood circulation. Here, we identified a steroidal saponin trillin from Dioscorea nipponica, which showed robust anti-hyperlipidemic effects.
Rats were induced for hyperlipidemia and subjected to the drug treatment. The anti-hyperlipidemic effects of trillin were evaluated by different biochemical assays.
In hyperlipidemic rat model, fed with high-fat diet, the blood levels of cholesterol, triglyceride, low density lipoprotein (LDL) and high density lipoprotein (HDL) were increased. The intra-peritoneal administration of trillin into those rats significantly improved the bleeding and blood coagulation time, and in parallel the treatment restored the levels of cholesterol, glyceride, LDL and HDL back to the normal condition. In addition, the administration of trillin in rats exerted beneficial effects in improving the levels of lipid peroxidation and superoxide dismutase activity.
This was the first time to reveal the anti-hyperlipidemic and anti-oxidative effects of trillin. These results would be important in developing food supplements for health improvements and therapeutic drugs against hyperlipidemia and cardiovascular diseases in future.
Journal of ethnopharmacology 11/2011; 139(1):214-20. · 2.32 Impact Factor
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ABSTRACT: Acetylcholinesterase (AChE) anchors onto cell membranes by a transmembrane protein PRiMA (proline-rich membrane anchor) as a tetrameric form in vertebrate brain. The assembly of AChE tetramer with PRiMA requires the C-terminal “t-peptide”
in AChE catalytic subunit (AChET). Although mature AChE is well known N-glycosylated, the role of glycosylation in forming the physiologically active PRiMA-linked AChE tetramer has not been studied.
Here, several lines of evidence indicate that the N-linked glycosylation of AChET plays a major role for acquisition of AChE full enzymatic activity but does not affect its oligomerization. The expression
of the AChET mutant, in which all N-glycosylation sites were deleted, together with PRiMA in HEK293T cells produced a glycan-depleted PRiMA-linked AChE tetramer
but with a much higher Km value as compared with the wild type. This glycan-depleted enzyme was assembled in endoplasmic reticulum but was not transported
to Golgi apparatus or plasma membrane.
Journal of Biological Chemistry 09/2011; 286(38):32948-32961. · 4.77 Impact Factor
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ABSTRACT: Flavonoids, a group of natural compounds found in a variety of vegetables and herbal medicines, have been intensively reported
on regarding their estrogen-like activities and particularly their ability to affect bone metabolism. Here, different subclasses
of flavonoids were screened for their osteogenic properties by measuring alkaline phosphatase activity in cultured rat osteoblasts.
The flavone baicalin derived mainly from the roots of Scutellaria baicalensis showed the strongest induction of alkaline phosphatase activity. In cultured osteoblasts, application of baicalin increased
significantly the osteoblastic mineralization and the levels of mRNAs encoding the bone differentiation markers, including
osteonectin, osteocalcin, and collagen type 1α1. Interestingly, the osteogenic effect of baicalin was not mediated by its
estrogenic activity. In contrast, baicalin promoted osteoblastic differentiation via the activation of the Wnt/β-catenin signaling
pathway; the activation resulted in the phosphorylation of glycogen synthase kinase 3β and, subsequently, induced the nuclear
accumulation of the β-catenin, leading to the transcription activation of Wnt-targeted genes for osteogenesis. The baicalin-induced
osteogenic effects were fully abolished by DKK-1, a blocker of Wnt/β-catenin receptor. Moreover, baicalin also enhanced the
mRNA expression of osteoprotegerin, which could regulate indirectly the activation of osteoclasts. Taken together, our results
suggested that baicalin could act via Wnt/β-catenin signaling to promote osteoblastic differentiation. The osteogenic flavonoids
could be very useful in finding potential drugs, or food supplements, for treating post-menopausal osteoporosis.
Journal of Biological Chemistry 08/2011; 286(32):27882-27893. · 4.77 Impact Factor
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ABSTRACT: Acetylcholinesterase (AChE) anchors onto cell membranes by a transmembrane protein PRiMA (proline-rich membrane anchor) as a tetrameric form in vertebrate brain. The assembly of AChE tetramer with PRiMA requires the C-terminal "t-peptide" in AChE catalytic subunit (AChE(T)). Although mature AChE is well known N-glycosylated, the role of glycosylation in forming the physiologically active PRiMA-linked AChE tetramer has not been studied. Here, several lines of evidence indicate that the N-linked glycosylation of AChE(T) plays a major role for acquisition of AChE full enzymatic activity but does not affect its oligomerization. The expression of the AChE(T) mutant, in which all N-glycosylation sites were deleted, together with PRiMA in HEK293T cells produced a glycan-depleted PRiMA-linked AChE tetramer but with a much higher K(m) value as compared with the wild type. This glycan-depleted enzyme was assembled in endoplasmic reticulum but was not transported to Golgi apparatus or plasma membrane.
Journal of Biological Chemistry 07/2011; 286(38):32948-61. · 4.77 Impact Factor
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ABSTRACT: Flavonoids, a group of natural compounds found in a variety of vegetables and herbal medicines, have been intensively reported on regarding their estrogen-like activities and particularly their ability to affect bone metabolism. Here, different subclasses of flavonoids were screened for their osteogenic properties by measuring alkaline phosphatase activity in cultured rat osteoblasts. The flavone baicalin derived mainly from the roots of Scutellaria baicalensis showed the strongest induction of alkaline phosphatase activity. In cultured osteoblasts, application of baicalin increased significantly the osteoblastic mineralization and the levels of mRNAs encoding the bone differentiation markers, including osteonectin, osteocalcin, and collagen type 1α1. Interestingly, the osteogenic effect of baicalin was not mediated by its estrogenic activity. In contrast, baicalin promoted osteoblastic differentiation via the activation of the Wnt/β-catenin signaling pathway; the activation resulted in the phosphorylation of glycogen synthase kinase 3β and, subsequently, induced the nuclear accumulation of the β-catenin, leading to the transcription activation of Wnt-targeted genes for osteogenesis. The baicalin-induced osteogenic effects were fully abolished by DKK-1, a blocker of Wnt/β-catenin receptor. Moreover, baicalin also enhanced the mRNA expression of osteoprotegerin, which could regulate indirectly the activation of osteoclasts. Taken together, our results suggested that baicalin could act via Wnt/β-catenin signaling to promote osteoblastic differentiation. The osteogenic flavonoids could be very useful in finding potential drugs, or food supplements, for treating post-menopausal osteoporosis.
Journal of Biological Chemistry 06/2011; 286(32):27882-93. · 4.77 Impact Factor
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Janis Y X Zhan,
Ken Y Z Zheng,
Kevin Y Zhu,
Cathy W C Bi,
Wendy L Zhang,
Crystal Y Q Du,
Qiang Fu,
Tina T X Dong, Roy C Y Choi,
Karl W K Tsim,
David T W Lau
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ABSTRACT: The roots of Angelica sinensis [Angelica Sinensis Radix (ASR)] have been used as a common health food supplement for women's care for thousands of years in China. According to Asian tradition, ASR could be processed with the treatment of wine, which subsequently promoted the biological functions of ASR. By chemical and biological assessments, an orthogonal array design was employed here to determine the roles of three variable parameters in the processing of ASR, including oven temperature, baking time, and flipping frequency. The results suggested that oven temperature and baking time were two significant factors, while flipping frequency was a subordinate factor. The optimized condition of processing with wine therefore was considered to be heating in an oven at 80 °C for 90 min with flipping twice per hour. Under the optimized processing conditions, the solubilities of ferulic acid and Z-ligustilide from ASR were markedly increased and decreased, respectively. In parallel, the biological functions of processed ASR were enhanced in both anti-platelet aggregation and estrogenic activation; these increased functions could be a result of the altered levels of ferulic acid and Z-ligustilide in wine-processed ASR. Thus, the chemical and biological assessment of the processed ASR was in full accordance with the Chinese old tradition.
Journal of Agricultural and Food Chemistry 05/2011; 59(11):6091-8. · 2.82 Impact Factor
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Ken Y Z Zheng, Roy C Y Choi,
Anna W H Cheung,
Ava J Y Guo,
Cathy W C Bi,
Kevin Y Zhu,
Qiang Fu,
Yingqing Du,
Wendy L Zhang,
Janis Y X Zhan,
R Duan,
David T W Lau,
Tina T X Dong,
Karl W K Tsim
[show abstract]
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ABSTRACT: Radix Astragali (RA) is commonly used as a health food supplement to reinforce the body vital energy. Flavonoids, including formononetin, ononin, calycosin, and calycosin-7-O-β-d-glucoside, are considered to be the major active ingredients within RA. Here, we provided different lines of evidence that the RA flavonoids stimulated the expression of erythropoietin (EPO), the central regulator of red blood cell mass, in cultured human embryonic kidney fibroblasts (HEK293T). A plasmid containing hypoxia response element (HRE), a critical regulator for EPO transcription, was tagged upstream of a firefly luciferase gene, namely, pHRE-Luc, which was being transfected into fibroblasts. The application of RA flavonoids onto the transfected cells induced the transcriptional activity of HRE. To account for the transcriptional activation after the treatment of flavonoids, the expression of hypoxia-inducible factor-1α (HIF-1α) was markedly increased: The increase was in both mRNA and protein levels. In addition, the degradation of HIF-1α was reduced under the effect of flavonoids. The regulation of HIF-1α therefore could account for the activation of EPO expression mediated by the RA flavonoids. The current results therefore reveal the function of this herb in enhancing hematopoietic functions.
Journal of Agricultural and Food Chemistry 02/2011; 59(5):1697-704. · 2.82 Impact Factor
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ABSTRACT: An effective way to determine the amount of different neurotransmitters is vital to the study of brain function. Here, a highly sensitive HPLC-MS/MS method was developed to simultaneously measure γ-aminobutyric acid, dopamine, epinephrine, norepinepherine, glutamate and serotonin in one sample. The quantification of the neurotransmitters was achieved by a tandem mass spectrometer using the selected reaction monitoring scan mode. The method validation included selectivity, linearity, accuracy, precision, stability, recovery and matrix effect. For the six neurotransmitters, the linear regression analysis was calibrated by deuterated internal standards with a R(2) of over 0.991, and the limit of detection (LOD) and the limit of quantification (LOQ) were from 2.5 to 500 pg/mg and 7.5 to 1000 pg/mg, respectively. This method was employed here to reveal different types and amounts of neurotransmitters simultaneously in adult and embryonic rat brains. Here, the change of dopamine concentration in embryonic and adult brain was from 0.071 to 0.760 ng/mg of brain tissue, GABA was from 207.643 to 445.148 ng/mg, glutamate was from 679.535 to 1408.920 ng/mg, serotonin was from 0.058 to 0.485 ng/mg and norepinepherine was from 0.054 to 0.290 ng/mg. For epinephrine, it was only detected in embryonic stage but not in adult, with the concentration at 0.241 ng/mg.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 02/2011; 879(11-12):737-42. · 2.78 Impact Factor
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ABSTRACT: Immunoglobulin superfamily (IgSF) proteins play a critical role in development of the nervous system. Here, a new member of IgSF gene family was cloned from rat brain, which was subsequently identified as rat homolog of Drosophila Kirre. This new molecule was named as rat Kirre (rKirre). We aimed to reveal the developmental expression of rKirre, both at mRNA and protein levels, in the central nervous system. The deduced amino acid sequence of rKirre showed a putative PDZ binding motif at the C-terminus, which provided a rationale for analyzing the co-localization of rKirre and post-synaptic density protein 95 (PSD-95) in cultured rat cortical neurons.
cDNA library screening was used in the isolation of cDNA. Northern blotting and Western blotting were used to reveal the levels of rKirre expression. In situ hybridization and immuno-fluorescent staining were used to determine the localization of rKirre.
The rKirre gene was found to be highly expressed in the cerebrum, hippocampus, cerebellum, brain stem and spinal cord of adult rats. In parallel, the protein level of rKirre was also increased in a developing cerebral cortex. In cultured rat cortical neurons, the amount of rKirre was significantly increased during neuronal differentiation. Immuno-cytofluorescent staining indicated that rKirre was present along the neurites of cortical neurons, and was co-localized with PSD-95.
These results suggested that rKirre might play an essential role in neuronal differentiation and development in the central nervous system.
Life sciences 01/2011; 88(13-14):590-7. · 2.56 Impact Factor
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ABSTRACT: Acetylcholinesterase (AChE) is responsible for the hydrolysis of the neurotransmitter, acetylcholine, in the nervous system. The functional localization and oligomerization of AChE T variant are depending primarily on the association of their anchoring partners, either collagen tail (ColQ) or proline-rich membrane anchor (PRiMA). Complexes with ColQ represent the asymmetric forms (A(12)) in muscle, while complexes with PRiMA represent tetrameric globular forms (G(4)) mainly found in brain and muscle. Apart from these traditional molecular forms, a ColQ-linked asymmetric form and a PRiMA-linked globular form of hybrid cholinesterases (ChEs), having both AChE and BChE catalytic subunits, were revealed in chicken brain and muscle. The similarity of various molecular forms of AChE and BChE raises interesting question regarding to their possible relationship in enzyme assembly and localization. The focus of this review is to provide current findings about the biosynthesis of different forms of ChEs together with their anchoring proteins.
Frontiers in Molecular Neuroscience 01/2011; 4:36.
