• Preventive Nutrition and Food Science
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• v.4 no.3
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• pp.209-214
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• 1999

In this study, the effectof ethanol and acetaldehyde on DNA binding activities of NF-$textsc{k}$B and AP-1 were evaluated in C6 rat glial cells. Both NF-$textsc{k}$B and AP-1 are important transcription factors for the expression of various cytokines in glial cells. Our data showed that neither ethanol nor acetaldehyde induced conspicuous cell death of C6 cells at clinically realistic concentrations. When the DNA binding activities of nuclear NF-$textsc{k}$B and AP-1 were estimated using electrophoretic mobility shift assay (EMSA), ethanol(0.3%) or acetaldehyde(1mM) induced transient activation of these transcription factors, which attained peak levels at 4~8 hours and declined to basal levels at 12 hours after treatement . The supershift analysis showed that the increased activities of NF-$textsc{k}$B in ethanol/acetaldehyde-treated C6 cells were due to the preferential induction of p65/p50 heterodimer complex. The DNA binding activities of these transcriptional factors decreased below basal levels when cells were cultured with either ethanol or acetaldehyde for 24 hours, and showed the inhibitory effect of chronic ehtanol /acetaldehyde treatment on the activities of these transsriptional factors. Our data indicate that either ethanol or acetaldehyde can induce functional changes of glial cells throught bi-directional modulation of NF-$textsc{k}$B and AP-1 DNA binding activities.

• Biomedical Science Letters
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• v.12 no.3
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• pp.275-279
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• 2006

It is demonstrated that cadmium has cytotoxic effect on glial cells, oxygen radicals are involved in cadmium-induced cytotoxicity. However, the toxic mechanism of cadmium is left unknown so far. The purpose of this study was to examine the cytotoxicity of $CdCl_2$ on $C_6$ glioma cells. The cytotoxicy was measured by cell viability via XTT assay in $C_6$ glioma cells. Colorimetric assay such as XTT assay is regarded as a very sensitive screening method for the determination of the cell viability on a lots of chemicals. In this study, $CdCl_2$ decreased cell viability according to the dose- and time dependent manners after $C_6$ glioma cells were treated with various concentrations of $CdCl_2$ for 48 hours. $IC_{90}\;and\;IC_{50}$ values for XTT assay was determined at $5{\mu}M\;and\;55{\mu}M$ of $CdCl_2$, respectively. These results suggest that $CdCl_2$ has highly cytotoxic effect on $C_6$glioma cells by the decrease of cell viability.

• Korean Journal of Agricultural Science
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• v.46 no.2
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• pp.369-379
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• 2019

Alzheimer's disease (AD) is the most common neurodegenerative disease associated with age, and amyloid beta ($A{\beta}$) is known to cause Alzheimer's disease. In the present study, we investigated the protective effects of Cirsium japonicum var. maackii extract and its fractions against $A{\beta}$-induced neurotoxicity in C6 glial cells. The cells treated with $A{\beta}_{25-35}$ showed a decrease in cell viability and an increase in reactive oxygen species (ROS) production compared with the non-treated cells. However, the cells treated with the C. japonicum var. maackii extract and its fractions increased the cell viability and inhibited the $A{\beta}$-induced ROS production. These results demonstrate the neuroprotective effects of C. japonicum var. maackii against $A{\beta}$. To further examine the protective mechanism, we measured inflammation and apoptosis related protein expressions. The cells treated with extract and fractions from C. japonicum var. maackii down-regulated inflammatory related proteins such as cyclooxygenase-2, interleukin $(IL)-1{\beta}$, and IL-6, and attenuated apoptosis related proteins including B-cell lymphoma-2 (Bcl-2) associated X protein/Bcl-2 ratio. In particular, the ethanol and ethylacetate fraction exhibited higher inhibitory effect against ROS production and apoptosis-related protein expressions among the extract and the other fractions. Therefore, this study demonstrated the protective effects of C. japonicum var. maackii extract and its fractions against $A{\beta}$-induced neurotoxicity in C6 glial cells through the regulation of oxidative stress, inflammation, and apoptosis, suggesting that it might have potential as a therapeutic for AD.

• Biomolecules & Therapeutics
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• v.17 no.4
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• pp.395-402
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• 2009

Insulin appears to play a role in brain physiology, and disturbances of cerebral insulin signalling and glucose homeostasis are implicated in brain pathology. The objective of the present study was to investigate the protective effects of insulin under conditions of oxidative stress induced by hydrogen peroxide ($H_2O_2$) in C6 glial cells. Insulin at concentration of $10^{-7}$ M could prevent 12 h $H_2O_2$-induced cell death. The formation of reactive oxygen species (ROS), nitric oxide (NO) and 2-thiobarbituric acid-reactive substances (TBARS) were significantly scavenged by insulin pre-treatment in C6 glial cells after $H_2O_2$-induced oxidative stress. Insulin significantly stimulated the phosphorylation of Akt in the cells and the activation of Akt was maintained in response to insulin under $H_2O_2$ incubation for 12 h. In conclusion, these results provide evidence that insulin acts as a free radical scavenger and stimulating Akt activity. These data suggest that insulin may be effective in degenerative diseases with oxidative stress.

• Nutrition Research and Practice
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• v.9 no.2
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• pp.123-128
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• 2015

BACKGROUND/OBJECTIVES: Natural products or active components with a protective effect against oxidative stress have attracted significant attention for prevention and treatment of degenerative disease. Oligonol is a low molecular weight polyphenol containing catechin-type monomers and oligomers derived from Litchi chinensis Sonn. We investigated the protective effect and its related mechanism of oligonol against oxidative stress. MATERIALS/METHODS: Oxidative stress in C6 glial cells was induced by hydrogen peroxide ($H_2O_2$) and the protective effects of oligonol on cell viability, nitric oxide (NO) and reactive oxygen species (ROS) synthesis, and mRNA expression related to oxidative stress were determined. RESULTS: Treatment with oligonol inhibited NO and ROS formation under cellular oxidative stress in C6 glial cells. In addition, it recovered cell viability in a dose dependent-manner. Treatment with oligonol also resulted in down-regulated mRNA expression related to oxidative stress, nuclear factor kappa-B (NF-${\kappa}B$) p65, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS), compared with the control group treated with $H_2O_2$. In particular, expression of NF-${\kappa}B$ p65, COX-2, and iNOS was effectively reduced to the normal level by treatment with $10{\mu}g/mL$ and $25{\mu}g/mL$ of oligonol. CONCLUSIONS: These results indicate that oligonol has protective activity against oxidative stress-induced inflammation. Oligonol might be a promising agent for treatment of degenerative diseases through inhibition of ROS formation and NF-${\kappa}B$ pathway gene expression.

• Korean Journal of Agricultural Science
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• v.45 no.3
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• pp.509-519
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• 2018

This study was investigated the anti-oxidant property and neuro-protective effect of Cirsium japonicum var. maackii (CJM) against oxidative stress in hydrogen peroxide ($H_2O_2$)-induced C6 glial cells. We measured the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, hydroxyl radical (${\cdot}OH$), and superoxide ($O_2{^-}$) radical scavenging activities of an ethanol extract and four fractions [n-Butanol, ethyl acetate (EtOAc), $CHCl_3$, and n-Hexane] from CJM. The results of this study show that the extract and all fractions from CJM had a dose-dependent DPPH radical scavenging activity. In particular, the EtOAc fraction exhibited the strongest scavenging effect with 88.23% at a concentration of $500{\mu}g/mL$. In addition, the EtOAc fraction from CJM also effectively scavenged ${\cdot}OH$ radicals and $O_2{^-}$ radicals, compared to other extract and fractions. In C6 glial cells, $H_2O_2$ markedly decreased the cell viability as well as increased lactate dehydrogenase (LDH) release and reactive oxygen species (ROS) production. However, the EtOAc fraction of CJM attenuated the cellular damage from the oxidative stress by elevating the cell viability and inhibiting the LDH release and ROS over-production compared with the $H_2O_2$-treated control group. Our findings indicate that the EtOAc fraction from CJM has antioxidant effect and neuro-protective effect against oxidative stress, suggesting that it can be used as a natural antioxidant and therapeutic agent for the prevention of neurodegenerative disorders.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.4
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• pp.1120-1128
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• 2004

Zinc ion has both essential and toxic effects on mammalian cells. The results demonstrated that the ability of zinc to act as an inducer of apoptosis in C6 glial cells. Incubation with 0.2 mM ZnCl₂ caused cell death that was characterized as apoptosis by internucleosomal DNA fragmentation, formation of apoptotic bodies, nuclear fragmentation and breakdown of the mitochondrial membrane potential. ZnCl₂-induced apoptosis of C6 glial cells was prevented by the addition of Sibjeondaebo-Tang and antioxidants including reduced glutathione, N-acetyl-L-cysteine. We further confirmed that ZnCl₂ decreased the intracellular levels of GSH as well as generation of H₂O₂ in C6 glial cells. In 2D-electrophoresis, computer-assisted comparative analysis of the respective silver stained spot patterns revealed 3 groups with strongly decreased intensity by ZnCl₂. Whereas, 3 groups with increasing intensity were recovered by Sibjeondaebo-Tang. These results suggest that Sibjeondaebo-Tang may function as an antioxidant against free radicals and be applicable to the treatment of brain cells against oxidative stress.

• Korean Journal of Pharmacognosy
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• v.47 no.3
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• pp.251-257
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• 2016

In this study, the radical scavenging activity and protective effect of ethanol extract from leaf of Engelhardtia chrysolepis HANCE (ECE) against oxidative stress were investigated under in vitro and cellular system. ECE showed strong radical scavenging activities in 1,1-diphenyl-2-picrylhydrazyl, hydroxyl(${\cdot}OH$) and nitric oxide(NO) radical as a concentration-dependent manner. Particularly, strong scavenging activity against the ${\cdot}OH$ and NO radical were observed with the $IC_{50}$ value of $1.30{\mu}g/ml$ and $12.61{\mu}g/ml$, respectively. Furthermore, the cellular oxidative stress was induced by amyloid beta($A{\beta}_{25-35}$) in C6 glial cells. The treatment of $A{\beta}_{25-35}$ to C6 glial cells generated high levels of reactive oxygen species(ROS) and declined cell viability. However, production of ROS was decreased by the treatment of ECE. In addition, the cell viability was significantly increased at each concentration(10, 25, $50{\mu}g/ml$) as dose-dependent manner. The Alzheimer's disease-related protein expressions in $A{\beta}_{25-35}$-treated C6 glial cells were analyzed. The ECE treatment inhibited expression of amyloid precursor protein(APP), C-terminal fragment-${\beta}(CTF-{\beta})$, ${\beta}$-site APP cleaving enzyme(BACE), phosphorylated tau(p-tau) proteins in C6 glial cells induced by $A{\beta}_{25-35}$. The present study indicated that ECE has strong radical scavenging activity and neuroprotective effect through attenuating oxidative stress.

• Journal of Applied Biological Chemistry
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• v.64 no.1
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• pp.69-74
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• 2021

Chronic alcohol is responsible for oxidative stress and neurodegenerative diseases such as dementia. In the present study, we investigated the antioxidant activity and protective effects of seed of Carthamus tinctorius L. on ethanol-induced C6 glial cells. Antioxidant effect of seed of C. tinctorius L. was measured by scavenging activity of 1,1-diphenyl-2-prcrylhydrazy (DPPH), hydroxyl radical (·OH), superoxide radical, and nitric oxide. The seed of C. tinctorius L. extract showed significant radical scavenging activities in a concentration-dependent manner. In particular, it revealed strong DPPH and ·OH scavenging activity, displaying more than 80% at 500 and 100 ㎍/mL, respectively. Treatment of 500 mM ethanol to C6 glial cell led to decline of cell viability and elevation of reactive oxygen species (ROS) generation. However, seed of C. tinctorius L.-treated groups significantly increased cell viability and decreased ROS levels, compared to ethanol-induced control group. These results suggest that seed of C. tinctorius L. would have protective effect against neuronal oxidative stress induced by alcohol.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.1967-1971
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• 2016

Background: In tumor cells, aberrant differentiation programs have been described. Several neuronal proteins have been found associated with morphological neuronal-glial changes in breast cancer (BCa). These neuronal proteins have been related to mechanisms that are involved in carcinogenesis; however, this regulation is not well understood. Microtubule-associated protein-tau (MAP-Tau) has been describing in BCa but not its variants. This finding could partly explain the neuronal-glial morphology of BCa cells. Our aim was to determine mRNA expression of MAP-tau variants 2, 4 and 6 in breast cancer cell lines. Materials and Methods: Cultured cell lines MCF-10A, MDA-MB-231, SKBR3 and T47D were observed under phase-contrast microscopy for neural morphology and analyzed for gene expression of MAP-Tau transcript variants 2, 4 and 6 by real-time PCR. Results: Regarding morphology like neural/glial cells, T47D line shown more cells with these features than MDA-MB-231 and SKBR. In another hand, we found much greater mRNA expression of MAP-Tau transcript variants 2, and to a lesser extent 4 and 6, in T47D cells than the other lines. In conclusion, regulation of MAP-Tau could bring about changes in cytoskeleton, cell morphology and motility; these findings cast further light on neuronal transdifferentiation in BCa.