• Journal of Life Science
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• v.25 no.5
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• pp.594-600
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• 2015

Protein-protein interactions have a critical role in the regulation of many cellular functions. Postsynaptic density-95/disks large/zonula occludens-1 (PDZ) domain is one of domains that mediate protein-protein interactions. PDZ domains typically bind to the specific motif at the carboxyl (C)-terminal end of partner proteins. Multi-PDZ domain protein 1 (MUPP1), which has 13 PDZ domains, serves a scaffolding function for structure proteins and signaling proteins, but the cellular function of MUPP1 has not been fully elucidated. We used the yeast two-hybrid system to identify proteins that interact with PDZ domains of MUPP1. We found an interaction between MUPP1 and muskelin. Muskelin was recently identified as a GABA_A receptor (GABA_AR) α1 subunit binding protein and known to have a role in receptor endocytosis and degradation. Muskelin bound to the 3^rd PDZ domain, but not to other PDZ domains of MUPP1. The C-terminal end of muskelin was essential for the interaction with MUPP1 in the yeast two-hybrid assay. When co-expressed in HEK-293T cells, muskelin but not the C-terminal deleted muskelin was co-immunoprecipitated with MUPP1. In addition, MUPP1 co-localized with muskelin at the same subcellular region in cells. These findings collectively suggest that MUPP1 or its interacting proteins could modulate GABA_AR trafficking and turnover through the interaction with muskelin.

• Journal of Acupuncture Research
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• v.17 no.4
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• pp.5-17
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• 2000

To research the characteristics of ion currents induced by Bujaijung-tang and Bojungikgi-tang, nystatin-perforated patch clamp technique under voltage-c(amp condition was used. Periaqueductal gray neuron was dissociated from Sprauge-Dawley rat, 10-15 days old. Cytotoxicity of Bujaijung-tang and Bojungikgi-tang showed incubation time and concentration dependent manner. Ion current activated by Bujaijung-tang and Bojungikgi-tang were inhibited by bicuculline and strychnine and CNQX. It can be suggested that Bujaijung-tang and Bojungikgi-tang modulate inhibitory and excitatory neurotransmitters-, GABA, glycine and non-NMDA, acticvated ion channels. Modulatory effect of Bujaijung-tang and Bojungikgi-tang was more greater in inhibitory neurotransmitters. Low concentration of Bujaijung-tang which dose not elicit ion current itself, activated GABA and glycine induced chloride currents. In this study, we can found that the activation of Bujaijung-tang and Bojungikgi-tang on non-NMDA subtypes of glutamate receptor is its major action mechanism and can be used as very effective Herb treatment on Myasthenia gravis patient.

• Natural Product Sciences
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• v.26 no.1
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• pp.1-9
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• 2020

Flavonoids are mainly contained in the vegetables and medicinal herbs. Until now, over 5,000 kinds of flavonoid have been identified and their biological activities have been reported. Among them, we are interested in oroxylin A and spinosin because of their specific structures having bulky group at C-6 of ring A. Oroxylin A is contained in the Scutellaria baicalensis and exhibits cognitive enhancing activity as a GABA_A receptor antagonist, which is different from those of mainly contained in the S. baicalenis, baicalein or wogonin. Spinosin is isolated from Zizyphus jujuba var. spinosa and mainly studied as a hypnotic or anxiolytic agent because of traditional knowledge about its original herb. As far as we know, the cognitive function of spinosin was first identified by our group. In this review, we discuss how such flavonoids exert their pharmacological activities associated with cognitive function based on the receptor binding study and behavioral studies. Traditional knowledge and reverse pharmacology may be addressed in the research field of phytochemical pharmacology and useful to unveil the secret of phytochemicals.

• Korean Journal of Pharmacognosy
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• v.44 no.3
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• pp.281-285
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• 2013

Ethanol extract of Gastrodia elata fermented with Lactobacillus brevis was highly effective on the duration of pentobarbital hypnosis in mice. Pretreatment of mice with ethanol extract of the fermented Gastrodia elata (200 mg/kg, p.o.) prolonged markedly the duration of pentobarbital sleeping time and reduced the sleep latency. The mechanism of the extract of the fermented Gastrodia elata was investigated to inhibit the binding of $^3H$-Flumazenil, a selective benzodiazepine receptor antagonist, to benzodiazepine receptor of mice cortices. $IC_{50}$ value from displacement of $^3H$-Flumazenil binding was 62 ${\mu}g/mL$ at the treatment of the fermented Gastrodia elata. Therefore, these finding, such as increase of sleeping time and reduction of sleep latency, was examined by elevated concentration of GABA and parishin C, which were increased by Lactobacillus brevis.

• Proceedings of the Korean Biophysical Society Conference
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• 1998.06a
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• pp.35-35
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• 1998

Catfish retina contains cone- and rod-horizontal cells. Only the cone-horizontal cell (cone-HC) has an axon and axon terminal. We compared the distribution of excitatory and inhibitory receptors in axon terminals and somata to begin to learn about the distinct functions of these two structures.(omitted)

• Journal of Ginseng Research
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• v.24 no.3
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• pp.134-137
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• 2000

Spontaneous bursting activity was studied in rat thalamocortical slices using extracellular field potential recording to test the potential utilization of ginsenoside Rb$_1$ in controlling overactivated neural systems. In order to induce bursting activity, slices were perfused with Mg$\^$2+/-free artificial cerebrospinal fluid (ACSF). Two major types of spontaneous bursting activity, simple thalamocortical burst complexes (sTBCs) and complex thalamocortical burst complexes (cTBCs), were recorded in Mg$\^$2+/ -free ACSF. Ginsenoside Rb$_1$ selectively suppressed cTBCs. Duration and occurrence rate of cTBCs were reduced by 87.3${\pm}$10.2% and 85.3${\pm}$ 14.7% in the presence of 90 ${\mu}$M ginsenoside Rb$_1$ respectively, while amplitude and intraburst frequency were slightly changed by ginsenoside Rb$_1$. In contrast, ginsenoside Rb$_1$was much less effective in reducing duration and occurrence rate of sTBCs. We also tested effects of ginsenoside Rb$_1$ on bursting activity in the presence of a GABA$\sub$A/ receptor antagonist, bicuculline methiodide (BMI). Ginsenoside Rb$_1$ had no effect in suppressing BMI-induced bursting activities. These results suggest that ginsenoside Rbi may be useful in controlling seizure-like bursting activity under pathological conditions.

• Biomolecules & Therapeutics
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• v.24 no.2
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• pp.115-122
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• 2016

Sleep, which is an essential part of human life, is modulated by neurotransmitter systems, including gamma-aminobutyric acid (GABA) and dopamine signaling. However, the mechanisms that initiate and maintain sleep remain obscure. In this study, we investigated the relationship between melatonin (MT) and dopamine D2-like receptor signaling in pentobarbital-induced sleep and the intracellular mechanisms of sleep maintenance in the cerebral cortex. In mice, pentobarbital-induced sleep was augmented by intraperitoneal administration of 30 mg/kg MT. To investigate the relationship between MT and D2-like receptors, we administered quinpirole, a D2-like receptor agonist, to MT- and pentobarbital-treated mice. Quinpirole (1 mg/kg, i.p.) increased the duration of MT-augmented sleep in mice. In addition, locomotor activity analysis showed that neither MT nor quinpirole produced sedative effects when administered alone. In order to understand the mechanisms underlying quinpirole-augmented sleep, we measured protein levels of mitogen-activated protein kinases (MAPKs) and cortical protein kinases related to MT signaling. Treatment with quinpirole or MT activated extracellular-signal-regulated kinase 1 and 2 (ERK1/2), p38 MAPK, and protein kinase C (PKC) in the cerebral cortex, while protein kinase A (PKA) activation was not altered significantly. Taken together, our results show that quinpirole increases the duration of MT-augmented sleep through ERK1/2, p38 MAPK, and PKC signaling. These findings suggest that modulation of D2-like receptors might enhance the effect of MT on sleep.

• Journal of Pharmaceutical Investigation
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• v.35 no.3
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• pp.193-199
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• 2005

Gabapentin is an antiepileptic drug that is structurally similar to ${\gamma}-aminobutyric$ acid (GABA), but does not interact with the GABA receptor. It does not bind significantly to plasma proteins, and is excreted to unchanged form in the urine. The purpose of the present study was to evaluate the bioequivalence of two gabapentin capsules, $Neurontin^{TM}$ capsule 300 mg (Pfizer Pharm. Co., Ltd.) and Kuhnil $Gabapentin^{TM}$ capsule 300 mg (Kuhnil Pharm. Co., Ltd), according to the guidelines of the Korea Food and Drug Administration (KFDA). The release of gabapentin from the two gabapentin formulations in vitro was tested using KP VIII Apparatus II method with various dissolution media (pH 1.2, 4.0, 6.8 buffer solution and water). Twenty six healthy male subjects, $22.46{\pm}1.86$ years in age and $67.64{\pm}7.24$ kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After a single capsule containing 300 mg as gabapentin was orally administered, blood samples were taken at predetermined time intervals and the concentrations of gabapentin in serum were determined using HPLC with fluorescence detector. The dissolution profiles of two formulations were similar at all dissolution media. In addition, the pharmacokinetic parameters such as $AUC_t$, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t$, $C_{max}$ and untransformed $T_{max}$. The results showed that the differences between two formulations based on the reference drug, $Neurontin^{TM}$ capsule 300 mg, were -2.03, -0.43 and 4.29% for $AUC_t$, $C_{max}$ and $T_{max}$, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log 0.8 to log 1.25 $(e.g.,\;log\;0.89{\sim}log\;1.09\;and\;log\;0.91{\sim}log\;1.09$ for $AUC_t$ and $C_{max}$, respectively). Thus, the criteria of the KFDA bioequivalence guideline were satisfied, indicating Kuhnil $Gabapentin^{TM}$ capsule 300 mg was bioequivalent to $Neurontin^{TM}$ capsule 300 mg.

• Journal of Pharmacopuncture
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• v.15 no.3
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• pp.19-30
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• 2012

Objectives: Many efforts have shown multi-oncologic roles of galectin-3 for cell proliferation, angiogenesis, and apoptosis. However, the mechanisms by which galectin-3 is involved in cell proliferation are not yet fully understood, especially in human colon cancer cells. Methods: To cluster genes showing positively or negatively correlated expression with galectin-3, we employed human colon cancer cell lines, SNU-61, SNU-81, SNU-769B, SNU-C4 and SNU-C5 in high-throughput gene expression profiling. Gene and protein expression levels were determined by using real-time quantitative polymerase chain reaction (PCR) and western blot analysis, respectively. The proliferation rate of human colon cancer cells was measured by using a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Results: Expression of ${\gamma}$-aminobutyric acid B receptor 1 (GABABR1) showed a positive correlation with galectin-3 at both the transcriptional and the translational levels. Down-regulation of galectin-3 decreased not only GABABR1 expression but also the proliferation rate of human colon cancer cells. However, Korean herbal extract, HangAmDan-B (HAD-B), decreased expression of GABABR1 without any expressional change of galectin-3, and offset ${\gamma}$-aminobutyric acid (GABA)-enhanced human colon cancer cell proliferation. Conclusions: Our present study confirmed that GABABR1 expression was regulated by galectin-3. HAD-B induced galectin-3-independent down-regulation of GABABR1, which resulted in a decreased proliferation of human colon cancer cells. The therapeutic effect of HAD-B for the treatment of human colon cancer needs to be further validated.

• Animal Bioscience
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• v.37 no.8
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• pp.1345-1354
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• 2024

Objective: The objective of this study was to identify candidate genes that play important roles in skeletal muscle development in ducks. Methods: In this study, we investigated the transcriptional sequencing of embryonic pectoral muscles from two specialized lines: Liancheng white ducks (female) and Cherry valley ducks (male) hybrid Line A (LCA) and Line C (LCC) ducks. In addition, prediction of target genes for the differentially expressed mRNAs was conducted and the enriched gene ontology (GO) terms and Kyoto encyclopedia of genes and genomes signaling pathways were further analyzed. Finally, a protein-to-protein interaction network was analyzed by using the target genes to gain insights into their potential functional association. Results: A total of 1,428 differentially expressed genes (DEGs) with 762 being up-regulated genes and 666 being down-regulated genes in pectoral muscle of LCA and LCC ducks identified by RNA-seq (p<0.05). Meanwhile, 23 GO terms in the down-regulated genes and 75 GO terms in up-regulated genes were significantly enriched (p<0.05). Furthermore, the top 5 most enriched pathways were ECM-receptor interaction, fatty acid degradation, pyruvate degradation, PPAR signaling pathway, and glycolysis/gluconeogenesis. Finally, the candidate genes including integrin b3 (Itgb3), pyruvate kinase M1/2 (Pkm), insulin-like growth factor 1 (Igf1), glucose-6-phosphate isomerase (Gpi), GABA type A receptor-associated protein-like 1 (Gabarapl1), and thyroid hormone receptor beta (Thrb) showed the most expression difference, and then were selected to verification by quantitative real-time polymerase chain reaction (qRT-PCR). The result of qRT-PCR was consistent with that of transcriptome sequencing. Conclusion: This study provided information of molecular mechanisms underlying the developmental differences in skeletal muscles between specialized duck lines.