• The Korea Journal of Herbology
• /
• v.20 no.3
• /
• pp.29-41
• /
• 2005

Objectives : The use of natural products with therapeutic properties is as ancient as human civilisation and, for a long time, mineral, plant and animal products were the main sources of drugs. Catalposide, the major iridoid glycoside isolated from the stem bark of Catalpa ovata G. Don (Bignoniceae) has been shown to possess anti-microbial and anti-tumoral properties. Heme oxygenase-1 (HO-1) is a stress response protein and is known to play a protective role against the oxidative injury. In this study, we examined whether catalposide could protect Neuro 2A cells, a kind of neuronal cell lines, from oxidative damage through the induction of HO-1 protein expression and HO activity. We also examined the effects of catalposide on the productions of tumor necrosis $factor-{\alpha}\;(TNF-{\alpha})$ and nitric oxide (NO) on RAW 264.7 macrophages activated with the endotoxin lipopolysaccharide. Methods : HO-1 expression in Neuro 2A cells was measured by Western blotting analysis. NO and $TNF--{\alpha}$ produced by RAW 264.7 macrophage were measured by Griess reagent and enzyme-linked immunosorbent assay, respectively. Results : The treatment of the cells with catalposide resulted in dose- and time-dependent up-regulations of both HO-1 protein expression and HO activity. Catalposide protected the cells from hydrogen peroxide-induced cell death. The protective effect of catalposide on hydrogen peroxide-induced cell death was abrogated by zinc protoporphyrin IX, a HO inhibitor. Additional experiments revealed the involvement of CO in the cytoprotective effect of catalposide-induced HO-1. In addition, catalposide inhibited the productions of $TNF--{\alpha}$ and NO with significant decreases in mRNA levels of $TNF--{\alpha}$ and inducible NO synthase. Conclusions : Our results indicate that catalposide is a potent inducer of HO-1 and HO-1 induction is responsible for the catalposide-mediated cytoprotection against oxidative damage and that catalposide may have therapeutic potential in the control of inflammatory disorders.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.24 no.1
• /
• pp.91-95
• /
• 2010

Alzheimer's disease (AD) is characterized pathologically by the presence of intracellular neurofibrillary tangles and deposition of ${\beta}$-amyloid (A${\beta}$) peptides. It is urgent to develop effective therapies for the treatment of AD, since our society rapidly accelerate aging. A${\beta}$ peptides have been believed to be neurotoxic and now are also considered to have affects on the mechanism of memory formation, which are generated by processing of amyloid precursor protein (APP). In this study, effects of Styrax Liquides (SL) on the metabolism of APP were analyzed. SL inhibited the secretion of A${\beta}$ from the Neuro2a cell line (APPswe cell) expressing a mutation of APPswe. Immunoblotting study showed that it inhibited ${\beta}$-site APP cleaving enzyme (BACE) from the APPswe cells. We suggest that SL inhibits APP metabolism and A${\beta}$ generation by the means of BACE inhibitory mechanism. This is the first report that SL inhibits the secretion of A${\beta}$ peptides from neuroblastoma cells.

• The Korean Journal of Physiology and Pharmacology
• /
• v.13 no.3
• /
• pp.251-256
• /
• 2009

Previous observations suggest that Bis, a Bcl-2-binding protein, may playa role the neuronal and glial differentiation in vivo. To examine this further, we investigated Bis expression during the in vitro differentiation of P19 embryonic carcinoma cells induced by retinoic acid (RA). Western blotting and RT-PCR assays showed that Bis expression was temporarily decreased during the free floating stage and then began to increase on day 6 after the induction of differentiation. Double immunostaining indicated that Bis-expressing cells do not express several markers of differentiation, including NeuN, MAP-2 and Tuj-1. However, some of the Bis-expressing cells also were stained with GFAP-antibodies, indicating that Bis is involved glial differentiation. Using an shRNA strategy, we developed bis-knock down P19 cells and compared them with control P19 cells for the expression of NeuroD, Mash-1 and GFAP during RA-induced differentiation. Among these, only GFAP induction was significantly attenuated in Pl9-dnbis cells and the population showing GFAP immunoreactivity was also decreased. It is noteworthy that distribution of mature neurons and migrating neurons was disorganized, and the close association of migrating neuroblasts with astrocytes was not observed in P19-dnbis cells. These results suggest that Bis is involved in the migration-inducing activity of glial cells.

• Biomedical Science Letters
• /
• v.24 no.2
• /
• pp.64-75
• /
• 2018

CCN3 (also known as NOV, Nephroblastoma overexpressed) proteins are involved in various pathologies during different developmental stages. We have previously shown that intracellular levels and normal extracellular secretion of CCN3 are important for neuronal differentiation. Furthermore, we demonstrated that a single amino acid in the CCN3 TSP-1 domain is important for extracellular secretion and that palmitoylation of CCN3 is required in this process. However, the effect of abnormal CCN3 accumulation on cells remains to be studied. Here, we found mutations in the TSP-1 domain of CCN3 that led to intracellular accumulation and abnormal aggregation of CCN3. It was observed that this mutation resulted in a phenomenon similar to neurodegeneration when overexpressed in the developing mouse cortex. This mutation also confirmed the activation of apoptotic gene expression in Neuro2a cells. In addition, we confirmed the in vivo transcriptional changes induced by this mutation using microarray analysis. We observed a significant increase in the expression of Anp32a, an apoptosis-related gene. Collectively, these results indicate that a single mutation in CCN3 can lead to abnormal cell death if it shows intracellular accumulation and abnormal aggregation.

• Reproductive and Developmental Biology
• /
• v.28 no.4
• /
• pp.247-252
• /
• 2004

Human embryonic stem (ES) cells are derived from the inner cell mass of the preimplantation embryo. Human ES cells have the capacity to differentiate into various types of cells in the body. Human ES cells are indefinite source of cells for cell therapy in various degenerative disorders including neuronal disorders. Directed differentiation of human ES cells is a prerequisite for their clinical application. The objective of this study is to develop the culture condition for the derivation of neural precursor cells from human ES cells. Neural precursor cells were derived from human ES cells in a stepwise culture condition. Neural precursor cells in the form of neural rosette structures developed into neurospheres when cultured in suspension. Suspension culture of neurospheres has been maintained over 4 months. Expressions of nestin, soxl, sox2, pax3 and pax6 transcripts were upregulated during differentiation into neural precursor cells by RT-PCR analysis. In contrast, expression of oct4 was dramatically downregulated in neural precursor cells. Immunocytochemical analyses of neural precursor cells demonstrated expression of nestin and SOX1. When induced to differentiate on an adhesive substrate, neuro-spheres were able to differentiate into three lineages of neural systems, including neurons, astrocytes and oligo-dendrocytes. Transcripts of sox1 and pax6 were downregulated during differentiation of neural precursor cells into neurons. In contrast, expression of map2ab was elevated in the differentiated cells, relative to those in neural precursor cells. Neurons derived from neural precursor cells expressed NCAM, Tuj1, MAP2ab, NeuN and NF200 in immunocytochemical analyses. Presence of astrocytes was confirmed by expression of GFAP immuno-cytochemically. Oligodendrocytes were also observed by positive immuno-reactivities against oligodendrocyte marker O1. Results of this study demonstrate that a stepwise culture condition is developed for the derivation of neural precursor cells from human ES cells.

• Biomedical Science Letters
• /
• v.24 no.4
• /
• pp.305-310
• /
• 2018

Microglia are emerging as critical regulators of innate immune responses in AD and other neurodegenerative disorders, highlighting the importance of understanding their molecular and cellular mechanisms. We attempted to determine the role of crosstalk signaling between $IFN-{\gamma}$ and $TGF-{\beta}$ in $A{\beta}$ clearance by microglia cells. We used in vitro and in vivo mouse models that recapitulated acute and chronic aspects of microglial responses to $A{\beta}$ peptides. We showed that crosstalk signaling between $TGF-{\beta}$ and Smad2 was an important mediator of neuro-inflammation. These findings suggest that microglial $TGF-{\beta}$ activity enhances the pathological progression to AD. As $TGF-{\beta}$ displays broad regulatory effects on beneficial microglial functions, the activation of inflammatory crosstalk signaling between $TGF-{\beta}$ and Smad2 may be a promising strategy to restore microglial functions, halt the progression of $A{\beta}$-driven pathology, and prevent AD development.

• Journal of Microbiology and Biotechnology
• /
• v.21 no.4
• /
• pp.366-373
• /
• 2011

We characterized the proteomes of murine N2a cells following infection with three rabies virus (RV) strains, characterized by distinct virulence phenotypes (i.e., virulent BD06, fixed CVS-11, and attenuated SRV9 strains), and identified 35 changes to protein expression using two-dimensional gel electrophoresis in whole-cell lysates. The annotated functions of these proteins are involved in various cytoskeletal, signal transduction, stress response, and metabolic processes. Specifically, a-enolase, prx-4, vimentin, cytokine-induced apoptosis inhibitor 1 (CIAPIN1) and prx-6 were significantly up-regulated, whereas Trx like-1 and galectin-1 were down-regulated following infection of N2a cells with all three rabies virus strains. However, comparing expressions of all 35 proteins affected between BD06-, CVS-11-, and SRV9-infected cells, specific changes in expression were also observed. The up-regulation of vimentin, CIAPIN1, prx-4, and 14-3-3 ${\theta}/{\delta}$, and down-regulation of NDPK-B and HSP-1 with CVS and SRV9 infection were ${\geq}2$ times greater than with BD06. Meanwhile, Zfp12 protein, splicing factor, and arginine/serine-rich 1 were unaltered in the cells infected with BD06 and CVS-11, but were up-regulated in the group infected with SRV9. The proteomic alterations described here may suggest that these changes to protein expression correlate with the rabies virus' adaptability and virulence in N2a cells, and hence provides new clues as to the response of N2a host cells to rabies virus infections, and may also aid in uncovering new pathways in these cells that are involved in rabies infections. Further characterization of the functions of the affected proteins may contribute to our understanding of the mechanisms of RV infection and pathogenesis.

• The Korean Journal of Physiology and Pharmacology
• /
• v.9 no.5
• /
• pp.275-282
• /
• 2005

By using differential display, we identified one of the genes encoding the multi-subunit complex protein V-ATPase, c subunit gene (ATP6L), and showed alterations of the gene expression by oxidative stresses. Expression of the ATP6L gene in Neuro-2A cells was increased by the treatment with $H_2O_2$ and incubation in hypoxic chamber, implying that the expression of the ATP6L gene is regulated by oxidative stresses. To examine mechanisms involved in the regulation of the gene expression by oxidative stresses, the transcriptional activity of the rat ATP6L promoter was studied. Transcription initiation site was determined by primer extension analysis and DNA sequencing, and promoter of the rat ATP6L and its deletion clones were constructed in reporter assay vector. Significant changes of the promoter activities in Neuro-2A cells were observed in two regions within the proximal 1 kbp promoter, and one containing a suppressor was in -195 to -220, which contains GC box that is activated by binding of Sp1 protein. The suppression of promoter activity was lost in mutants of the GC box. We confirmed by electrophoretic mobility shift and supershift assays that Sp1 protein specifically binds to the GC box. The promoter activity was not changed by the $H_2O_2$ treatment and incubation in hypoxic chamber, however, $H_2O_2$ increased the stability of ATP6L mRNA. These data suggest that the expression of the ATP6L gene by oxidative stresses is regulated at posttranscriptional level, whereas the GC box is important in basal activities of the promoter.

• Journal of Photoscience
• /
• v.9 no.2
• /
• pp.475-478
• /
• 2002

In zoological research, penetration of light has been reported of the frontal bones of fish, birds, and reptiles, suggesting the existence of physiologically direct photic routes to frontal lobes and/or deep parts of the brain. We studied the influences of frontal exposure to photodiode light on frontal alpha wave and peripheral NK cells. Repetitive exposure of the subject's forehead to a red light diode (660nm) significantly increased the effective amplitude of the frontal alpha waves (using a mean frequency with a range of +1.0 Hz), peripheral NK activity, and the level of CD57-CD16+. Frontal alpha wave activity and the level of CD57-CD16+ increased, suggesting the possibility of a non-invasive procedure for the activation of the frontal lobe and the increase of NK cells. This light is considered to penetrate the frontal bones of humans directly, and to act on the frontal lobe and/or other immunological regulatory centers in the brain, resulting in some neuro-immunological changes.

• Journal of Life Science
• /
• v.25 no.6
• /
• pp.656-662
• /
• 2015

Natural products and natural product structures play a general and highly significant role in drug discovery and development process because it has various merits and potentials for new drug source that have extensive clinical experience, development time contraction, excellent stability and safety. In several neurological disorders, neuronal death and excessive activation of microglia (neuro-inflammation) are observed. A number of drug discovery-related neuronal cell death and neuro-inflammation was studied from natural products, respectively. However, until now, it has not been possible to study dual-protection molecules recorded in the Natural Product library. In the present study, using the natural product-derived library of the Institute for Korea Traditional Medical Industry, we investigated dual-protective molecules against glutamate (a classical excitatory neurotransmitter)-induced oxidative stress mediated neuronal cell death and LPS-induced excessive activated microglial cells (immune cells of the brain). Chrysophanol, extracted from Rheum palmatum, had dual-protective effects against both glutamate-induced neuronal cell death and LPS-induced NO production, triggering proinflammatory cytokines and microglia activation and resulting in neuroinflammation. Flow-cytometry analysis revealed that chrysophanol had a scavenger effect, scavenging glutamate- and LPS-induced reactive oxygen species (ROS) produced by neuronal and microglial cells, respectively. Based on the present study, chrysophanol may have an important protective role against neuronal cell death and neuroinflammation in the brain. The results may be helpful for studying drug development candidates for treating central nervous system disorders.