• Journal of Life Science
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• v.25 no.8
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• pp.953-959
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• 2015

Optogenetics is the combination of optical and molecular strategies to control designated molecular and cellular activities in living tissues and cells using genetically encoded light-sensitive proteins. It involves the use of light to rapidly gate the membrane channels that allows for ion movement. Optogenetics began with the placing of light-sensitive proteins from green algae inside specific types of brain cells. The cells can then be turned on or off with pulses of blue and yellow light. Using the naturally occurring algal protein Channelrhodopsin-2 (ChR2), a rapidly gated light-sensitive cation channel, the number and frequency of action potentials can be controlled. The ChR2 provides a way to manipulate a single type of neuron while affecting no others, an unprecedented specificity. This technology allows the use of light to alter neural processing at the level of single spikes and synaptic events, yielding a widely applicable tool for neuroscientists and biomedical engineers. An improbable combination of green algae, lasers, gene therapy and fiber optics made it possible to map neural circuits deep inside the brain with a precision that has never been possible before. This will help identify the causes of disorders like depression, anxiety, schizophrenia, addiction, sleep disorder, and autism. Optogenetics could improve upon existing implanted devices that are used to treat Parkinson’s disease, obsessive-compulsive disorder and other ailments with pulses of electricity. An optogenetics device could hit more specific subsets of brain cells than those devices can. Applications of optogenetic tools in nonneuronal cells are on the rise.

• Molecular & Cellular Toxicology
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• v.4 no.2
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• pp.106-112
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• 2008

Parkinson's disease (PD) progresses severely by a gradual loss of dopaminergic neurons in the substantia nigra (SN). Epidemiological studies showed that the incidences of PD were reduced by smoking of which the major component, nicotine might be neuroprotective. But the function of nicotine, which might suppress the incidences of PD, is still unknown. Fortunately, recently it was reported that a glial reaction and inflammatory processes might participate in a selective loss of dopaminergic neurons in the SN. The levels of tumour necrosis factor (TNF)-${\alpha}$ synthesised by astrocytes and microglia are elevated in striatum and cerebrospinal fluid (CSF) in PD. TNF-${\alpha}$ kills the cultured dopaminergic neurons through the apoptosis mechanism. TNF-${\alpha}$ release from glial cells may mediate progression of nigral degeneration in PD. Nicotine pretreatment considerably decreases microglial activation with significant reduction of TNF-${\alpha}$ mRNA expression and TNF-${\alpha}$ release induced by lipopholysaccharide (LPS) stimulation. Thus, this study was intended to explore the role of nicotine pretreatment to inhibit the expressions of TNF-${\alpha}$ mRNA in human fetal astrocytes (HFA) stimulated with IL-$1{\beta}$. The results are as follows: HFA were pretreated with 0.1, 1, and $10{\mu}g/mL$ of nicotine and then stimulated with IL-$1{\beta}$ (100 pg/mL) for 2h. The inhibitory effect of nicotine on expressions of TNF-${\alpha}$ mRNA in HFA with pretreated $0.1{\mu}g/mL$ of nicotine was first noted at 8hr, and the inhibitory effect was maximal at 12 h. The inhibitory effect at $1{\mu}g/mL$ of nicotine was inhibited maximal at 24 h. Cytotoxic effects of nicotine were noted above $10{\mu}g/mL$ of nicotine. Moreover, Nicotine at 0.1, 1 and $10{\mu}g/mL$concentrations significantly inhibited IL-$1{\beta}$-induced TF-${\kappa}B$ activation. Collectively, these results indicate that in activated HFA, nicotine may inhibit the expression of TNF-${\alpha}$ mRNA through the pathway which suppresses the NF-${\kappa}B$ activation. This study suggests that nicotine might be neuroprotective to dopaminergic neurons in the SN and reduce the incidences of PD.

• Development and Reproduction
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• v.15 no.2
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• pp.143-150
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• 2011

The objective of this study was to determine the effect of exercise on a hemiparkinsonian rat model. Nigrostriatal dopamine cell lesions were produced by injecting 6-hydroxydopamine at the left medial forebrain bundle of rats. In this study, the rats were divided into the following 4 groups: the control group without any exercise, experimental group I with aqua-exercise (Exp I), experimental group II with balance exercise (Exp II) and experimental group III with complex exercise (aqua-exercise+balance exercise; (Exp III)). Exercises were applied to all the experimental groups after the operation. In order to observe the dopaminergic cell loss, we assessed the level of tyrosine hydroxylase (TH) expression in the midbrain of rats, and performed the apomorphine-induced rotation test at postoperative days (PDs) 7, 14, and 21. Experimental groups had significantly higher TH-immunoreactivity and behavioral performance than the control group. However, there was no difference in TH-immunoreactivity and behavioral performance across the experimental groups. These results suggest that the application of aqua-exercise and balance exercise could suppress dopaminergic cell loss in the substantia nigra of rat brains and could increase behavioral recovery in hemiparkinsonian rats.

• Journal of the Korean Applied Science and Technology
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• v.35 no.1
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• pp.194-204
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• 2018

This study was to investigate the effect of the extract(KP-HE) from Kalopanax pictus(KP) fermented with Hericium erinaceum(HE) mycelium on oxidative modification of neurofilament-L(NF-L) which is closely related to neurodegenerative disorders. The oxidative modification of NF-L was induced by AAPH producing peroxyl radicals in solution, and KP, HE, and KP-HE was investigated. KP and HE did not protect NF-L against peroxyl radical-mediated NF-L modification whereas KP-HE significantly prevented NF-L modification induced by peroxyl radical. KP-HE inhibited the formation of dityrosine in oxidative modification of NF-L and stimulated the peroxyl radical scavenging activity. The effects of KP, HE, and KP-HE on the modification of NF-L by tetrahydropapaveroline(THP), a neurotoxin found in patients with Parkinson's disease was investigated. KP-HE also prevented THP-mediated NF-L modification as compared to KP and HE. In addition, KP-HE significantly inhibited the formation of dityrosine in oxidative modified NF-L and enhanced the inhibition of reactive oxygen species(ROS) was generated by THP. The results suggested that KP-HE can contribute to protected cell from oxidative stress was induced by ROS and neurotoxin. Therefore, KP-HE could potentially be used as a valuable functional food ingredient to prevent neurodegenerative disorders.

• Biomolecules & Therapeutics
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• v.21 no.3
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• pp.222-228
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• 2013

Although the role of ${\alpha}$-synuclein aggregation on Parkinson's disease is relatively well known, the physiological role and the regulatory mechanism governing the expression of ${\alpha}$-synuclein are unclear yet. We recently reported that ${\alpha}$-synuclein is expressed and secreted from cultured astrocytes. In this study, we investigated the effect of valproic acid (VPA), which has been suggested to provide neuroprotection by increasing ${\alpha}$-synuclein in neuron, on ${\alpha}$-synuclein expression in rat primary astrocytes. VPA concentration-dependently increased the protein expression level of ${\alpha}$-synuclein in cultured rat primary astrocytes with concomitant increase in mRNA expression level. Likewise, the level of secreted ${\alpha}$-synuclein was also increased by VPA. VPA increased the phosphorylation of Erk1/2 and JNK and pretreatment of a JNK inhibitor SP600125 prevented the VPA-induced increase in ${\alpha}$-synuclein. Whether the increased ${\alpha}$-synuclein in astrocytes is involved in the reported neuroprotective effects of VPA awaits further investigation.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1152-1156
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• 2009

Silent information regulator 2 (Sir2) or sirtuins are NAD(+)-dependent deacetylases, which hydrolyze the acetyllysine residues. In mammals, sirtuins are classified into seven different classes (SIRT1-7). SIRT1 was reported to be involved in age related disorders like obesity, metabolic syndrome, type II diabetes mellitus and Parkinson’s disease. Activation of SIRT1 is one of the promising approaches to treat these age related diseases. In this study, we have used HipHop module of CATALYST to identify a series of pharmacophore models to screen SIRT1 enhancing molecules. Three molecules from Sirtris Pharmaceuticals were selected as training set and 607 sirtuin activator molecules were used as test set. Five different hypotheses were developed and then validated using the training set and the test set. The results showed that the best pharmacophore model has four features, ring aromatic, positive ionization and two hydrogen-bond acceptors. The best hypothesis from our study, Hypo2, screened high number of active molecules from the test set. Thus, we suggest that this four feature pharmacophore model could be helpful to screen novel SIRT1 activator molecules. Hypo2-virtual screening against Maybridge database reveals seven molecules, which contains all the critical features. Moreover, two new scaffolds were identified from this study. These scaffolds may be a potent lead for the SIRT1 activation.

• KSBB Journal
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• v.20 no.1 s.90
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• pp.21-25
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• 2005

Paraquat, a widely used herbicide, has been suggested as a potential risk factor for Parkinson's disease. Heme oxygenase-1(HO-1), a marker for oxidative stress and endoplasmic reticulum(ER) stress, is known to catalyze heme to biliverdin, carbon monoxide and free iron in response to various stimuli. Here we show that paraquat activates HO-1 expression in a time-and dose-dependent manner in substantia nigra(SN) dopaminergic neuronal cells. Activation of Ho-1 by paraquat was regulated primarily at the level of gene transcription. Deletion analysis of the promoter and the 5' distal enhancers, E1 and E2, of the HO-1 gene revealed that the E2 enhancer is a potent inducer of the paraquat-dependent Ho-1 gene expression in dopamninergic neuronal cells. Mutational analysis of the E2 enhacer further demonstrated that the transcription factor activator protein-1(AP-1) plays an important role in mediating paraquat-induced HO-1 gene transcription. Moreover, using specific inhibitors of the mitogen-activated protein kinases(MAPKs), we investigated the role of paraquat and MAPKs for HO-1 gene regulation in dopaminergic cells. The c-Jun N-terminal kinase(JNK) inhibitor SP600125 significantly suppressed the expression of HO-1 by paraquat. All these results demonstrate that induction of HO-1 by paraquat requies the activation of the AP-1 and JNK pathway.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.12 no.4
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• pp.413-418
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• 2019

Studies are now actively underway to confirm the degree of treatment and rehabilitation of patients with brain-related diseases (dementia, schizophrenia, depression, Parkinson's disease). Among them, Transcranial magnetic stimulation (TMS) is widely used in treatment because it is a technique that is used for noninvasive brain neuron control in patients with brain disorders. It can be seen that muscle fatigue of normal people increases during Transcranial magnetic stimulation. Therefore, in this paper, our purpose is to build an EMG measurement system to measure motor neuron-induced response during transcranial magnetic stimulation and We identify a motor-neutral response system using tendency in the RMS graph. As an experimental method, the Raw Data received through the surface EMG device and analyzed by RMS technique, after the contraction and relaxation movement of the biceps brachii. As a result of the experiment, we confirmed the trend of rising RMS graph, and it will can be used to determine the self-stimulation intensity for each individual in consideration of the data of the motor-neutral response.

• Journal of the Korean Society of Radiology
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• v.15 no.4
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• pp.555-564
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• 2021

Thalamus is known to play an important role in the regulation of nerve function. Thalamus, located in the center of the brain, is involved in sleep, arousal, and emotional regulation, and has been reported to be associated with multiple sclerosis, essential tremors, and neurodegenerative diseases such as Parkinson's disease. In addition, it has been reported that iron deposits in the thalamus can cause depressive symptoms with age. Although there are discrepancies between studies, it can be deduced that the thalamus region has a clear effect on neurological disorders due to a strong relationship between the thalamus and neurological functions such as emotional control and processing. Through tractography analysis, the connectivity between the detailed areas of each subcortical region was investigated in the form of a matrix, showing strong connectivity and weak interhemispheric connectivity. In the 59> group, the WM connectivity of thalamus was found to be weaker than those of the two groups. Comparisons between the two groups showed that the young groups (10-39 and 40-59) had higher connection intensity than the 59> group and that statistically significant differences in 3 connection pathways were found in each hemisphere. A decrease in thalamus-related connection strength in aging has shown that it can affect emotional and neurological disorders such as anxiety and depression, and network measurements can help assess cognitive impairment across clinical conditions.

• The Journal of Korean Medicine
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• v.43 no.2
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• pp.1-7
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• 2022

Objectives: Bee venom (BV) is a widely used therapy in Traditional East Asian Medicine (TEAM). We previously reported that BV was clinically effective for treating Parkinson's disease, that phospholipase A₂ (PLA₂) was the main component of BV, and that it induced regulatory T cells (Tregs) by binding CD206 on dendritic cells (DCs). Therefore, we aimed to reconfirm our findings in human blood samples and investigate the relationship between CD206⁺ DCs and clinical syndrome differentiation in TEAM. Methods: We surveyed 100 subjects with questionnaires on cold-heat patternization and obtained their blood samples. The obtained human peripheral blood monocytes (hPBMCs) were washed with phosphate-buffered saline (PBS). After resuspension with ex vivo media, numbers of cells were counted. Tregs were counted after culturing the samples in a 37℃ CO₂ incubator for 72 h. Results: We divided the subjects into a relatively high CD206⁺ group or a relatively low CD206⁺ group. The heat factor scores of high CD206⁺ group were significantly higher than that of low CD206⁺ group (high vs low: 239.2 ± 54.1 vs 208.4 ± 55.1, p=0.023). After culturing with PLA₂, Tregs increased in the high CD206⁺ group but decreased in the low CD206⁺ group. Conclusion: In this study, we reconfirm that CD206⁺ DCs induced Treg differentiation by incubating human blood samples with PLA₂ and that they showed an association with syndrome differentiation, especially with heat patterns, in TEAM. A heat pattern in TEAM might be one indication for PLA₂ therapy because its score was elevated in the high CD206⁺ group.