• The Korean Journal of Physiology and Pharmacology
• /
• v.12 no.4
• /
• pp.131-135
• /
• 2008

The profile of membrane currents was investigated in differentiated neuronal cells derived from human neural stem cells (hNSCs) that were obtained from aborted fetal cortex. Whole-cell voltage clamp recording revealed at least 4 different currents: a tetrodotoxin (TTX)-sensitive $Na^+$ current, a hyperpolarization-activated inward current, and A-type and delayed rectifier-type $K^+$ outward currents. Both types of $K^+$ outward currents were blocked by either 5 mM tetraethylammonium (TEA) or 5 mM 4-aminopyridine (4-AP). The hyperpolarization-activated current resembled the classical $K^+$ inward current in that it exhibited a voltage-dependent block in the presence of external $Ba^{2+}$ (30 ${\mu}$M) or $Cs^+$ (3${\mu}$M). However, the reversal potentials did not match well with the predicted $K^+$ equilibrium potentials, suggesting that it was not a classical $K^+$ inward rectifier current. The other $Na^+$ inward current resembled the classical $Na^+$ current observed in pharmacological studies. The expression of these channels may contribute to generation and repolarization of action potential and might be regarded as functional markers for hNSCs-derived neurons.

• Fisheries and Aquatic Sciences
• /
• v.23 no.9
• /
• pp.24.1-24.9
• /
• 2020

Brown alga (Ishige okamurae; IO) dietary supplements have been reported to possess anti-diabetic properties. However, the effects of IO supplements have not been evaluated on glucose metabolism in the pancreas and skeletal muscle. C57BL/6 N male mice (age, 7 weeks) were arranged in five groups: a chow diet with 0.9% saline (NFD/saline group), high-fat diet (HFD) with 0.9% saline (HFD/saline group). high-fat diet with 25 mg/kg IO extract (HFD/25/IOE). high-fat diet with 50 mg/kg IO extract (HFD/50/IOE), and high-fat diet with 75 mg/kg IO extract (HFD/75/IOE). After 4 weeks, the plasma, pancreas, and skeletal muscle samples were collected for biochemical analyses. IOE significantly ameliorated glucose tolerance impairment and fasting and 2 h blood glucose level in HFD mice. IOE also stimulated the protein expressions of the glucose transporters (GLUTs) including GLUT2 and GLUT4 and those of their related transcription factors in the pancreases and skeletal muscles of HFD mice, enhanced glucose metabolism, and regulated blood glucose level. Our results suggest Ishige okamurae extract may reduce blood glucose levels by improving glucose metabolism in the pancreas and skeletal muscle in HFD-induced diabetes.

• Molecules and Cells
• /
• v.39 no.9
• /
• pp.669-679
• /
• 2016

N-acetyl-D-glucosamine kinase (GlcNAc kinase or NAGK) primarily catalyzes phosphoryl transfer to GlcNAc during amino sugar metabolism. Recently, it was shown NAGK interacts with dynein light chain roadblock type 1 (DYNLRB1) and upregulates axo-dendritic growth, which is an enzyme activity-independent, non-canonical structural role. The authors examined the distributions of NAGK and NAGK-dynein complexes during the cell cycle in HEK293T cells. NAGK was expressed throughout different stages of cell division and immunocytochemistry (ICC) showed NAGK was localized at nuclear envelope, spindle microtubules (MTs), and kinetochores (KTs). A proximity ligation assay (PLA) for NAGK and DYNLRB1 revealed NAGK-dynein complex on nuclear envelopes in prophase cells and on chromosomes in metaphase cells. NAGK-DYNLRB1 PLA followed by Lis1/NudE1 immunostaining showed NAGK-dynein complexes were colocalized with Lis1 and NudE1 signals, and PLA for NAGK-Lis1 showed similar signal patterns, suggesting a functional link between NAGK and dynein-Lis1 complex. Subsequently, NAGK-dynein complexes were found in KTs and on nuclear membranes where KTs were marked with CENP-B ICC and nuclear membrane with lamin ICC. Furthermore, knockdown of NAGK by small hairpin (sh) RNA was found to delay cell division. These results indicate that the NAGK-dynein interaction with the involvements of Lis1 and NudE1 plays an important role in prophase nuclear envelope breakdown (NEB) and metaphase MT-KT attachment during eukaryotic cell division.

• Biomedical Science Letters
• /
• v.15 no.1
• /
• pp.37-45
• /
• 2009

Insect cell cultures have become important tools in the production of biological substances for use in a variety of research, human and veterinary medicine, and pest control applications. These applications often require the introduction of foreign DNA into the cells and have generally used methods originally developed for use with human and other mammalian cell cultures. While these methods can be successfully employed, they are often less efficient with insect cells and frequently involve complex procedures or require specialized equipment. Even when they do work, they may require substantial modification because of differences in the culture medium or growth patterns of insect cells. In this study, We have optimized transfection conditions of Sf9 cell line using insect expression vector pIZT/V5-His which expresses green fluorescent protein effectively. Human stem cell factor (hSCF) is a glycoprotein that plays a key role in hematopoiesis acting both as a positive and negative regulator, often in synergy with other cytokines. It also plays a key role in mast cell development, gametogenesis, and melanogenesis. It can exist in membrane-bound form and in proteolytically released soluble form. As determined by an enzyme-linked immunosorbent assay performed, hSCF level in supernatant averaged 995ng/ml. The human hSCF was partially purified by immunoaffinity chromatography and analyzed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. The results show that the hSCF has N-linked carbohydrate and corresponds to the soluble form, at or about 223 amino acids in length. The findings suggest functional importance for soluble hSCF in cells.

• Molecules and Cells
• /
• v.37 no.4
• /
• pp.322-329
• /
• 2014

N-acetylglucosamine kinase (GlcNAc kinase or NAGK; EC 2.7.1.59) is highly expressed and plays a critical role in the development of dendrites in brain neurons. In this study, the authors conducted structure-function analysis to verify the previously proposed 3D model structure of GlcNAc/ATP-bound NAGK. Three point NAGK mutants with different substrate binding capacities and reaction velocities were produced. Wild-type (WT) NAGK showed strong substrate preference for GlcNAc. Conversion of Cys143, which does not make direct hydrogen bonds with GlcNAc, to Ser (i.e., C143S) had the least affect on the enzymatic activity of NAGK. Conversion of Asn36, which plays a role in domain closure by making a hydrogen bond with GlcNAc, to Ala (i.e., N36A) mildly reduced NAGK enzyme activity. Conversion of Asp107, which makes hydrogen bonds with GlcNAc and would act as a proton acceptor during nucleophilic attack on the ${\gamma}$-phosphate of ATP, to Ala (i.e., D107A), caused a total loss in enzyme activity. The overexpression of EGFP-tagged WT or any of the mutant NAGKs in rat hippocampal neurons (DIV 5-9) increased dendritic architectural complexity. Finally, the overexpression of the small, but not of the large, domain of NAGK resulted in dendrite degeneration. Our data show the effect of structure on the functional aspects of NAGK, and in particular, that the small domain of NAGK, and not its NAGK kinase activity, plays a critical role in the upregulation of dendritogenesis.

• Fisheries and Aquatic Sciences
• /
• v.26 no.6
• /
• pp.406-422
• /
• 2023

Sarcopenia is an age-related, progressive skeletal muscle disorder involving the loss of muscle mass and strength. Previous studies have shown that γ-aminobutyric acid (GABA) from fermented oysters aids in regulatory T cells (Tregs) cell expansion and function by enhancing autophagy, and concomitantly mediate muscle regeneration by modulating muscle inflammation and satellite cell function. The fermentation process of oysters not only increases the GABA content but also enhances the content of branched amino acids and free amino acids that aid the level of protein absorption and muscle strength, mass, and repair. In this study, the effect of GABA-enriched fermented sarco oyster extract (FSO) on reduced muscle mass and functions via Treg modulation and enhanced autophagy in aged mice was investigated. Results showed that FSO enhanced the expression of autophagy markers (autophagy-related gene 5 [ATG5] and GABA receptor-associated protein [GABARAP]), forkhead box protein 3 (FoxP3) expression, and levels of anti-inflammatory cytokines (interleukin [IL]-10 and transforming growth factor [TGF]-β) secreted by Tregs while reducing pro-inflammatory cytokine levels (IL-17A and interferon [IFN]-γ). Furthermore, FSO increased the expression of IL-33 and its receptor IL-1 receptor-like 1 (ST2); well-known signaling pathways that increase amphiregulin (Areg) secretion and expression of myogenesis markers (myogenic factor 5, myoblast determination protein 1, and myogenin). Muscle mass and function were also enhanced via FSO. Overall, the current study suggests that FSO increased autophagy, which enhanced Treg accumulation and function, decreased muscle inflammation, and increased satellite cell function for muscle regeneration and therefore could decrease the loss of muscle mass and function with aging.

• Anatomy and Cell Biology
• /
• v.56 no.2
• /
• pp.236-251
• /
• 2023

Alcohol consumption alongside combination antiretroviral therapy (cART) has attracted research interest, especially because of increasing male infertility. This study investigated the combined effects of alcohol and cART on testicular morphology, biomarkers of oxidative stress, inflammation, and apoptosis. Rats, weighing 330-370 g, were divided into four groups of six animals each; control, alcohol treated (A), cART, and alcohol plus cART treated (A+cART). Following 90 days treatment period, animals were euthanized, testis extracted, and routinely processed for histology and immunohistochemical analysis. Significantly decreased epithelial area fraction, increased luminal and connective tissue area fractions, and reduction of epithelial height and spermatocyte number, were recorded in the treated groups compared to control. Extensive seminiferous epithelial lesions including widened intercellular space, karyolysis, and sloughing of germinal epithelium were recorded in all the treated groups. Furthermore, upregulation of inducible nitric oxide synthase and 8-hydroxydeoxyguanosine, interleukin-6, and caspase 3 recorded in treated animals, was more significant in A+cART group. Also, the levels of interleukin-1β and tumor necrosis factor-α were more elevated in A and cART treated groups than in A+cART, while MDA was significantly elevated in cART and A+cART treated groups compared to control group. Altogether, the results indicate testicular toxicity of the treatments. It is concluded that consuming alcohol or cART induces oxidative stress, inflammation, and apoptosis in testis of rats, which lead to testicular structural and functional derangements, which are exacerbated when alcohol and cART are consumed concurrently. The result will invaluably assist clinicians in management of reproductive dysfunctions in male HIV/AIDS-alcoholic patients on cART.

• Applied Microscopy
• /
• v.32 no.4
• /
• pp.377-383
• /
• 2002

We have detected the murine zinc transporter, ZnT3, and zinc ions in the mouse choroid plexus by immunocytochemistry (ICC) and zinc selenium autometallography ($ZnSe^{AMG}$), respectively. BALB/c mice served as experimental animals. Routine floating ABC immunocytochemical procedures were used for the ZnT3 immunocytochemistry, and the mice were injected intraperitoneally (i.p.) with sodium selenide (10 mg/kg) for the zinc selenium autometallography. The choroid plexus showed weak immunoreactivity (Ir) for ZnT3. At high magnification, ZnT3-Ir was seen to be located in the choroid epithelium and the connective tissue of the capillaries. At the EM level, a high electron density of ZnT3-immunoreactivity was restricted to vesicle membranes as well as microvilli in the apical membrane. In contrast, immunostaining of ZnT3 was completely absent in the basolateral plasma membrane and other cell organelles. After silver enhancement, fine $ZnSe^{AMG}$ grains were observed in both the epithelial and endothelial cells of the choroid plexus. Few $ZnSe^{AMG}$ grains present in the cell bodies of the choroid epithelial cells were located in multivesicular bodies. It is striking that very many $ZnSe^{AMG}$ grains were observed in the endothelial cells of the capillaries. These findings establish the choroid plexus as a non-neuronal pool of zinc ions in the brain, although the functional significance of this pool is not clear. The choroid epithelium, however, may play an important role in the transportation of zinc between the CSF and brain tissue.

• Applied Microscopy
• /
• v.27 no.4
• /
• pp.357-372
• /
• 1997

To study the age-related morphological differences of the retinal pigment cells and Bruch's membrane of mouse, retinae of one week-old, five weeks-old, eight weeks-old, six months-old, twelve months-old, eighteen months-old, twenty-four months-old and thirty months-old ICR mice were dissected out under anesthesia. Pieces of the tissue taken from the posterior region of the retina were fixed in 2.5% glutaraldehyde-1.5% paraformaldehyde (0.1 M Millonig's phosphate buffer, pH 7.3), and 1% osmium tetroxide (0.1 M Millonig's phosphate buffer, pH 7.3), and embedded in araldite mixture. The ultrathin sections were stained with uranyl acetate and lead citrate, and were observed under a JEM 100 CX-II electron microscope. Observed results were as follows: 1. Retinae of one week old mouse exhibit that some parts of the pigment cell provided with basal foldings, whereas other parts of the one contain without basal foldings. After (ive weeks-old, all retinal pigment cells have the basal infoldings. 2. In the one week-old, stage 1 and stage 2 melanosomes were observed in the retinal pigments cells, but after five weeks-old, most of the retinal pigment cells contain some matured stage melanosomes (stage III and stage IV). 3. The phagosomes in the retinal pigment cells were increased during aging. 4. After eighteen months-old, electron dense materials are observed within the basal infoldings. 5. After eighteen months-old, the thickness of the Bruch's membrane is prominently increased. The thickness of the basal laminae of the pigment cell and the choriocapillary endothelium is more prominently increased as compared with that of the other components of the Bruch's membrane. 6. The thickness of the basal lamina of the pigment cell is more prominently increased as compared with that of the choriocapillary endothelium on aging. From the above results, it was suggested that the pigment cell and Bruch's membrane matures structurally In five weeks, and the function of the pigment cell is prominently suppressed around eighteen months-old, and thereafter the functional suppression is continued on aging.

• Journal of Korea Entertainment Industry Association
• /
• v.14 no.7
• /
• pp.651-658
• /
• 2020

The basic medical subjects are essential for the understanding of the major in the department of health science and are very important. Anatomy is one of the fundamental areas of medical education. On the other hand, the application of new teaching method is being attempted in various fields. Station rotation model, one of the blended learning, is also one of the popular teaching method. Station rotation model allows students to rotate through stations on a fixed schedule, where at least one of the stations is an online learning station. This study investigate the satisfaction of students when applying station rotation model to anatomy class. Each station in the station rotation model consisted of VR application learning, online problem solving, model observation and oral test. After applying station rotation model (2 weeks) to the 'Functional anatomy and Practice' course taken by 37 students of the'Department of Occupational Therapy'at H University, this study conducted a satisfaction survey compare with lecture class for students taking the course. At the result, station rotation model was significantly higher than lecture class in both understanding, interest, concentration and diversity degree. Based on these results, I suggest applying the station rotation model to the anatomy class because it also showed high satisfaction in that.