• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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• pp.84-84
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• 2003

Lead has long been considered as a toxic environmental pollutant, which severely damages central nervous system. Lead can cause hypo- and de-myelination, and glial cells are closely related with myelination or demyelination. Matrix metalloproteinases (MMPs) are proteolytic enzymes that are involved in the remodelling of the extracellular matrix in a variety of physiological and pathological processes. MMPs also seem to be important in the pathogenesis of inflammatory demyelinating diseases of the central and peripheral nervous system. In this study, we investigated whether lead affects MMP-9 expression in rat primary glial cells. Treatment of 0.1-5 ${\mu}$M lead dose- and time-dependently increased MMP-9 expression in rat primary glial cells. The activity of MMPs was determined using zymography. Lead activated Erk(1/2) but neither of the other endogenous MAP kinases, p38 or JNK. Inhibition of Erk(1/2) activation by PD98059, a MEK inihibitor, prevented lead-induced expression of MMP-9. The results of the present study suggest that lead intoxication may adversely affect brain function at least in part by inducing MMP-9 expression through Erk(1/2) activation in primary glial cells.

• Biomolecules & Therapeutics
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• 제12권4호
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• pp.209-214
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• 2004

Lead has long been considered as a toxic environmental pollutant that severely damages the central nervous system. In various neurogenerative diseases, actrocytes become activated by proinflammatory cytokines. In the present study, we investigated whether lead (Pb$^{2+}$) affects inducible nitric oxide synthase (iNOS) expression in activated glial cells. Rat primary glial cells were stimulated with lipopolysaccharide (LPS, 1 ${\mu}$g/ml) plus IFN$_{\gamma}$(100 U/ml). Pre-treatment of Pb$^{2+}$ increased nitric oxide (NO) production in LPS/IFN$_{\gamma}$-stimulated glial cells. Lead itself, however, suppressed the basal production of NO in control glial cells. Addition of the iNOS inhibitors L-NAME (1 mM) and L-NNA (800 ${\mu}$M) prevented the Pb$^{2+}$-induced increase in NO production. Western blot analysis showed that pre-treatment of Pb$^{2+}$ augmented LPS/IFN$_{\gamma}$-induced increase in iNOS immunoreactivity, which was well correlated with the increased NO production. In addition, pre-treatment of Pb$^{2+}$ synergistically increased the iNOS mRNA expression induced by LPS and IFN${\gamma}$. The present results indicate that lead intoxication adversely affect brain function by potentiating iNOS expression and NO production in activated glial cells observed in various neurodegenerative diseases.

• The Korean Journal of Physiology and Pharmacology
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• 제1권3호
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• pp.285-296
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• 1997

Injury to brain transforms resting astrocytes to their reactive form, the hallmark of which is an increase in glial fibrillary acidic protein (GFAP), the major intermediate filament protein of their cell type. The overall glial response after brain injury is referred to as reactive gliosis. Glial-neuronal interaction is important for neuronal migration, neurite outgrowth and axonal guidance during ontogenic development. Although much attention has been given to glial regulation of neuronal development and regeneration, evidences also suggest a neuronal influence on glial cell differentiation, maturation and function. The aim of the present study was to analyze the effects of glial-hippocampal neuronal co-culture on GFAP expression in the co-cultured astrocytes. The following antibodies were used for double immunostaining chemistry; mouse monoclonal antibodies for confirm neuronal cells, rabbit anti GFAP antibodies for confirm astrocytes. Primary cultured astrocytes showed the typical flat polygonal morphology in culture and expressed strong GFAP and vimentin. Co-cultured hippocampal neurons on astrocytes had phase bright cell body and well branched neurites. About half of co-cultured astrocytes expressed negative or weak GFAP and vimentin. After 2 hour glutamate (0.5 mM) exposure of glial-neuronal co-culture, neuronal cells lost their neurites and most of astrocytes expressed strong CFAE and vimentin. In Western blot analysis, total GFAP and vimentin contents in co-cultured astrocytes were lower than those of primary cultured astrocytes. After glutamate exposure of glial-neuronal co-culture, GFAP and vimentin contents in astrocytes were increased to the level of primary cultured astrocytes. These results suggest that neuronal cell decrease GFAP expression in co-cultured astrocytes and hippocampal neuronal-glial co-culture can be used as a reactive gliosis model in vitro for studying GFAP expression of astrocytes.

• IMMUNE NETWORK
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• 제13권4호
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• pp.141-147
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• 2013

Hypoxia has been shown to promote inflammation, including the release of proinflammatory cytokines, but it is poorly investigated how hypoxia directly affects inflammasome signaling pathways. To explore whether hypoxic stress modulates inflammasome activity, we examined the effect of cobalt chloride ($CoCl_2$)-induced hypoxia on caspase-1 activation in primary mixed glial cultures of the neonatal mouse brain. Unexpectedly, hypoxia induced by oxygen-glucose deprivation or $CoCl_2$ treatment failed to activate caspase-1 in microglial BV-2 cells and primary mixed glial cultures. Of particular interest, $CoCl_2$-induced hypoxic condition considerably inhibited NLRP3-dependent caspase-1 activation in mixed glial cells, but not in bone marrow-derived macrophages. $CoCl_2$-mediated inhibition of NLRP3 inflammasome activity was also observed in the isolated brain microglial cells, but $CoCl_2$ did not affect poly dA:dT-triggered AIM2 inflammasome activity in mixed glial cells. Our results collectively demonstrate that $CoCl_2$-induced hypoxia may negatively regulate NLRP3 inflammasome signaling in brain glial cells, but its physiological significance remains to be determined.

• Toxicological Research
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• 제12권2호
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• pp.203-211
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• 1996

Methanol has been widely used as an industrial solvent and environmental exposure to methanol would be expected to be increasing. In humans, methanol causes metabolic acidosis and damage to ocular system, and can lead to death in severe and untreated case. Clinical symptoms are attributed to accumulation of forrnic acid which is a metabolic product of methanol. In humans and primates, formic acid is accumulated after methanol intake but not in rodents due to the rapid metabolism of methanol. Neverthless, the developmental and reproductive toxicity were reported in rodents. Previous reports showed that perinatal exposure to ethanol produces a variety of damage in human central nervous system by direct neurotoxicity. This suggests that the mechanism of toxic symptoms by methanol in rodents might mimic that of ethanol in human. In the present study I hypothesized that methanol can also induce toxicity in neuronal cells. For the study, primary culture of rat hippocampal neurons and glias were empolyed. Hippocampal cells were prepared from the embryonic day-17 fetuses and maintained up to 7 days. Effect of methanol (10, 100, 500 and 1000 mM) on neurite outgrowth and cell viability was investigated at 0, 18 and 24 hours following methanol treatment. To study the changes in proliferation of glial cells, protein content was measured at 7 days. Neuronal cell viability in culture was not altered during 0-24 hours after methanol treatment. 10 and 100 mM methanol treatment significantly enhanced neurite outgrowth between 18-24 hours. 7-day exposure to 10 or 100 mM methanol significantly increased protein contents but that to 1000 mM methanol decreased in culture. In conclusion, methanol may have a variety of effects on growing and differentiation of neurons and glial cells in hippocampus. Treatment with low concentration of methanol caused that neurite outgrowth was enhanced during 18-24 hours and the numbers of glial cell were increased for 7 days. High concentration of methanol brought about decreased protein contents. At present, the mechanism responsible for the methanol- induced enhancement of neurite outgrowth is not clear. Further studies are required to delineate the mechanism possibly by employing molecular biological techniques.

• The Korean Journal of Physiology and Pharmacology
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• 제28권1호
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• pp.93-103
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• 2024

Satellite glial cells (SGCs), a major type of glial cell in the autonomic ganglia, closely envelop the cell body and even the synaptic regions of a single neuron with a very narrow gap. This structurally unique organization suggests that autonomic neurons and SGCs may communicate reciprocally. Glial Ca²⁺ signaling is critical for controlling neural activity. Here, for the first time we identified the machinery of store-operated Ca²⁺ entry (SOCE) which is critical for cellular Ca²⁺ homeostasis in rat sympathetic ganglia under normal and pathological states. Quantitative realtime PCR and immunostaining analyses showed that Orai1 and stromal interaction molecules 1 (STIM1) proteins are the primary components of SOCE machinery in the sympathetic ganglia. When the internal Ca²⁺ stores were depleted in the absence of extracellular Ca²⁺, the number of plasmalemmal Orai1 puncta was increased in neurons and SGCs, suggesting activation of the Ca²⁺ entry channels. Intracellular Ca²⁺ imaging revealed that SOCE was present in SGCs and neurons; however, the magnitude of SOCE was much larger in the SGCs than in the neurons. The SOCE was significantly suppressed by GSK7975A, a selective Orai1 blocker, and Pyr6, a SOCE blocker. Lipopolysaccharide (LPS) upregulated the glial fibrillary acidic protein and Toll-like receptor 4 in the sympathetic ganglia. Importantly, LPS attenuated SOCE via downregulating Orai1 and STIM1 expression. In conclusion, sympathetic SGCs functionally express the SOCE machinery, which is indispensable for intracellular Ca²⁺ signaling. The SOCE is highly susceptible to inflammation, which may affect sympathetic neuronal activity and thereby autonomic output.

• The Korean Journal of Physiology and Pharmacology
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• 제23권1호
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• pp.29-35
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• 2019

Decursin is a major biological active component of Angelica gigas Nakai and is known to induce apoptosis of metastatic prostatic cancer cells. Recently, other reports have been commissioned to examine the anticancer activities of this plant. In this study, we evaluated the inhibitory activity and related mechanism of action of decursin against glioblastoma cell line. Decursin demonstrated cytotoxic effects on U87 and C6 glioma cells in a dose-dependent manner but not in primary glial cells. Additionally, decursin increased apoptotic bodies and phosphorylated JNK and p38 in U87 cells. Decursin also down-regulated Bcl-2 as well as cell cycle dependent proteins, CDK-4 and cyclin D1. Furthermore, decursin-induced apoptosis was dependent on the caspase activation in U87 cells. Taken together, our data provide the evidence that decursin induces apoptosis in glioblastoma cells, making it a potential candidate as a chemotherapeutic drug against brain tumor.

• Journal of Ginseng Research
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• 제28권2호
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• pp.120-126
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• 2004

수천 년 동안 전통적 약제로 사용되어온 고려인삼은 중추신경계의 항상성을 유지하고 면역기능을 강화하는 효능을 나타내는 것으로 알려져 있다. 신경계질환의 진행이 대부분 염증 또는 면역반응을 수반하며, 이로 인하여 손상된 신경세포의 수복과정에 교세포 기원의 매개물질들이 기여하므로, 교세포에서의 cytokine 및 NO생성에 대한 연구는 신경기능과 신경면역기능의 조절 뿐 아니라 신경계 질환에 대한 연구의 초석이라고 할 수 있다. 따라서 본 연구에서는 고려인삼의 신경면역 및 염증반응 조절효과에 대하여 연구하고자 하였으며, 이를 위하여 흰쥐 대뇌피질의 교세포를 일차배양하며 고려인삼사포닌 분획을 처치하여 TNF-$\alpha$, IL-1$\beta$, 및 NO의 생성변동을 연구하였다. 백삼 사포닌은 50-500$\mu\textrm{g}$/ml 용량에서 TNF-$\alpha$와 IL-1$\beta$ 생성을 증가시켰으며, 미세교세포에서 iNOS 발현 및 NO생성을 유도하였고 성상세포의 stellation을 초래하였다. 특히 백삼사포닌 50-100 $\mu\textrm{g}$/ml는 세포독성을 거의 나타내지 않았으므로 이들 용량에 의한 교세포의 적절한 활성화가 중추신경계 면역기능 증가 및 염증반응 조절에 기여할 것으로 생각된다.

• 동의생리병리학회지
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• 제23권2호
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• pp.374-380
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• 2009

Samryungbaikchul-san(SRBCS) has been used in oriental medicine for the treatments of gastrointestinal and neurological disorders. Here, potential protective function of SRBCS was investigated in neural tissues in Alzheimer's disease(AD) mouse model. In primary cultured cells from the spinal cord of newborn rats, treatment of ${\beta}$-amyloid peptide elevated cell counts positive to glial fibrillary acidic protein(GFAP) or caspase 3 immunoreactivity, but the co-treatment of SRBCS reduced positive cell counts. In vivo administration of scopolamine, an inhibitor of muscarinic receptor, resulted in increases in the number of glial fibrillary acidic protein(GFAP) and caspase 3-positive cells in hippocampal subfields, which was then decreased by the treatment of SRBCS or acetylcholinesterase inhibitor galathamine. The present data suggest that SRBCS may play a protective role in damaged neural tissues caused by scopolamine treatments in mice.

• 대한의생명과학회지
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• 제10권4호
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• pp.325-332
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• 2004

Inflammatory factor such as Interleukin-1 play important roles in determining the fate of both acute and chronic neurological disorders. We investigated whether inhibitors of PKC or PTK can serve as pharmacological agents to reduce IL-I production and the mechanisms underlying their pharmacological effects in a mixed population of glia. Inhibitors of PKC such as H7, Go6976 and Ro31-8220 significantly reduced both the mRNA and protein levels of IL-1α and IL-β in lipopolysaccharide-activated primary glial cells. While the PTK inhibitor genistein also significantly reduced the production of these cytokines, it did not affect the expression of their mRNA. Taken together, inhibitors of PKC and PTK could serve as pharmacological agents to reduce IL-1 production. However, the mechanisms underlying their pharmacological effects are different. Our results provide evidence that inhibitors of protein kinases can serve as pharmacological agents to modulate IL-1 production in glial cell, and in turn, alleviate neuronal injury.