• 한국발생생물학회지:발생과생식
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• 제11권3호
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• pp.235-243
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• 2007

인간 제대혈 세포는 조혈모세포, 중간엽 줄기세포와내피전구세포를 풍부하게 포함하고 있다. 인간 제대혈 속의 중간엽 줄기세포는 조혈모세포와는 달리 다능성 줄기세포이며 신경세포로 분화할 수 있는 잠재성을 가지고 있다. 본 연구에서는 세포배양을 통해 제대혈의 중간엽 줄기세포를 신경세포와 콜린성 신경세포로 분화를 유도하였다. 중간엽 줄기세포를 신경세포로 분화시키기 위해 배양액에 dimethyl sulphoxide(DMSO)와 butylated hydroxyanisole(BHA)를 첨가하여 유도하였으며 basic fibroblast growth factor(bFGF), retinoic acid(RA), sonic hedgehog(Shh)를 처리하여 콜린성 신경세포로 분화시켰다. DMSO와 BHA에 처리된 중간엽 줄기세포가 빠르게 신경세포 모양으로 분화하는 것을 관찰하였으며, 이것은 면역조직학적 염색에서 신경세포 특이 표지인 $\beta$-tubulin III, 별아교세포에 대한 특이 표지인 GFAP, 희돌기아교세포에 대한 특이 표지인 Gal-C에 대해 양성반응을 나타내었고, 그 비율은 각각 $32.3{\pm}2.9%$, $11.0{\pm}0.9%,\;9.4{\pm}1.0%$였다. RT-PCR 분석에서 배양 단계에 따라 신경세포에 특이적인 표지 인자가 발현됨을 통해, 중간엽 줄기세포가 신경세포로 분화됨을 확인하였다. 또한, 중간엽 줄기세포에 bFGF, RA, Shh를 처리하여 콜린성 신경세포로 분화시켰을 때, 전체 중간엽 세포 중 $31.3{\pm}3.2%$가 신경세포 특이 표지인 $\beta$-tubulin III에 양성반응을 보였으며 이들 세포 중 $70.0{\pm}7.8%$가 콜린성 신경 특이 표지인 ChAT에 양성반응을 보였고, 이것은 Woodbury 방법에 의한 신경분화의 경우보다 3배 가량 높은 비율로 콜린성 신경의 분화를 유도한 것이다. 이러한 실험 결과들은 인간 제대혈의 중간엽 줄기세포가 콜린성 신경세포로 분화가 가능하고 이러한 잠재성을 가진 제대혈 중간엽 줄기세포는 퇴행성 신경질환에 대한 세포 치료제로서 가능성을 제시한다.

• 한국발생생물학회지:발생과생식
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• 제12권1호
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• pp.31-39
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• 2008

손상된 뇌신경조직내에서 신경줄기세포로부터 새로운 신경세포로의 분화가 상당히 제한되어 있어 이것이 손상된 뇌신경조직의 복구가 잘 이루어지지 않는 원인이라 여겨지고 있다. 본 연구에서는 세포배양을 통해 지방조직 중간엽 줄기세포를 도파민성 신경세포와 콜린성 신경세포로 분화를 유도하였다. 중간엽 줄기세포를 신경세포로 분화시키기 위해 N2배양액에 bFGF, EGF, dimethyl sulphoxide (DMSO)와 butylated hydroxyanisole (BHA)를 첨가하여 유도하였다. DMSO와 BHA에 처리된 중간엽 줄기세포가 빠르게 신경세포 모양으로 분화하는 것을 관찰하였으며, 이것은 면역조직학적 염색에서 신경세포 특이 표지인 $\beta$-tubulin III, 별아교세포에 대한 특이 표지인 GFAP, 흰돌기아교세포에 대한 특이 표지인 Gal-C에 대해 양성반응을 나타내었다. RT-PCR 분석에서 배양 단계에 따라 신경세포에 특이적인 표지 인자인 neuro D1, $\beta$-tubulin III, GFAP, nestin 등의 발현을 통해, 중간엽 줄기세포가 신경세포로 분화됨을 확인하였다. 그러나 중간엽줄기세포가 신경세포로 분화된 이후에는 줄기세포 표지인 SCF, C-kit와 stat-3 등은 발현되지 않았다. 또한, 중간엽줄기세포에 bFGF, SHH와 FGF8 등을 처리하면 도파민 신경세포로 분화하였다. 중간엽 줄기세포에 bFGF, RA, Shh를 처리하여 콜린성 신경세포로 분화시켰을 때, 신경세포 특이 표지인 $\beta$-tubulin III와 콜린성 신경 특이 표지인 ChAT에 양성반응를 보였다. 결론적으로 사람 지방조직의 중간엽 줄기세포가 도파민성과 콜린성 신경세포로 분화가 가능하고 이러한 잠재성을 가진 지방 유래 중간엽 줄기세포는 퇴행성 신경질환에 대한 세포 치료제로서 가능성을 제시한다.

• The Korean Journal of Physiology and Pharmacology
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• 제1권5호
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• pp.485-493
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• 1997

We investigated the effect of ${\alpha}-adrenergic$ and cholinergic receptor agonists on $Ca^{2+}$ current in adult rat trigeminal ganglion neurons using whole-cell patch clamp methods. The application of acetylcholine, carbachol, and oxotremorine ($50\;{\mu}M\;each$) produced a rapid and reversible reduction of the $Ca^{2+}$ current by $17{\pm}6%,\;19{\pm}3%,\;and\;18{\pm}4%$, respectively. Atropine, a muscarinic antagonist, blocked carbachol- induced $Ca^{2+}$ current inhibition to $3{\pm}1%$. Norepinephrine ($50\;{\mu}M$) reduced $Ca^{2+}$ current by $18{\pm}2%$, while clonidine ($50\;{\mu}M$), an ${\alpha}2-adrenergic$ receptor agonist, inhibited $Ca^{2+}$ current by only $4{\pm}1%$. Yohimbine, an ${\alpha}2-adrenergic$ receptor antagonist, did not block the inhibitory effect of norepinephrine on $Ca^{2+}$ current, whereas prazosin, an ${\alpha}1-adrenergic$ receptor antagonist, attenuated the inhibitory effect of norepinephrine on $Ca^{2+}$ current to $6{\pm}1%$. This pharmacology contrasts with ${\alpha}2-adrenergic$ receptor modulation of $Ca^{2+}$ channels in rat sympathetic neurons, which is sensitive to clonidine and blocked by yohimbine. Our data suggest that the modulation of voltage dependent $Ca^{2+}$ channel by norepinephrine is mediated via an α1-adrenergic receptor. Pretreatment with pertussis toxin (250 ng/ml) for 16 h greatly reduced norepinephrine- and carbachol-induced $Ca^{2+}$ current inhibition from $17{\pm}3%\;and\;18{\pm}3%\;to\;2{\pm}1%\;and\;2{\pm}1%$, respectively. These results demonstrate that norepinephrine, through an ${\alpha}1-adrenergic$ receptor, and carbachol, through a muscarinic receptor, inhibit $Ca^{2+}$ currents in adult rat trigeminal ganglion neurons via pertussis toxin sensitive GTP-binding proteins.

• Biomolecules & Therapeutics
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• 제22권3호
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• pp.176-183
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• 2014

Cognitive impairment is a result of dementia of diverse causes, such as cholinergic dysfunction and Alzheimer's disease (AD). Houttuynia cordata Thunb. (Saururaceae) has long been used as a traditional herbal medicine. It has biological activities including protective effects against amyloid beta ($A{\beta}$) toxicity, via regulation of calcium homeostasis, in rat hippocampal cells. To extend previous reports, we investigated the effects of water extracts of H. cordata herb (HCW) on tauopathies, also involving calcium influx. We then confirmed the effects of HCW in improving memory impairment and neuronal damage in mice with Ab-induced neurotoxicity. We also investigated the effects of HCW against scopolamine-induced cholinergic dysfunction in mice. In primary neuronal cells, HCW inhibited the phosphorylation of tau by regulating p25/p35 expression in $A{\beta}$-induced neurotoxicity. In mice with $A{\beta}$-induced neurotoxicity, HCW improved cognitive impairment, as assessed with behavioral tasks, such as novel object recognition, Y-maze, and passive avoidance tasks. HCW also inhibited the degeneration of neurons in the CA3 region of the hippocampus in Ab-induced neurotoxicity. Moreover, HCW, which had an $IC_{50}$ value of $79.7{\mu}g/ml$ for acetylcholinesterase inhibition, ameliorated scopolamine-induced cognitive impairment significantly in Y-maze and passive avoidance tasks. These results indicate that HCW improved cognitive impairment, due to cholinergic dysfunction, with inhibitory effects against tauopathies and cholinergic antagonists, suggesting that HCW may be an interesting candidate to investigate for the treatment of AD.

• Journal of Korean Neurosurgical Society
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• 제46권1호
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• pp.1-4
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• 2009

Objective: To report an unsuspected adaptive plasticity of single upper motor neurons and of primary motor cortex found after microsurgical connection of the spinal cord with peripheral nerve via grafts in paraplegics and focussed discussion of the reviewed literature. Methods: The research aimed at making paraplegics walk again, after 20 years of experimental surgery in animals. Amongst other things, animal experiments demonstrated the alteration of the motor endplates receptors from cholinergic to glutamatergic induced by connection with upper motor neurons. The same paradigm was successfully performed in paraplegic humans. The nerve grafts were put into the ventral-lateral spinal tract randomly, with out possibility of choosing the axons coming from different areas of the motor cortex. Results: The patient became able to selectively activate the re-innervated muscles she wanted without concurrent activities of other muscles connected with the same cortical areas. Conclusion: Authors believe that unlike in nerve or tendon transfers, where the whole cortical area corresponding to the transfer changes its function a phenomenon that we call "brain plasticity by areas". in our paradigm due to the direct connection of upper motor neurons with different peripheral nerves and muscles via nerve grafts motor learning occurs based on adaptive neuronal plasticity so that simultaneous contractions of other muscles are prevented. We propose to call it adaptive functional "plasticity by single neurons". We speculate that this phenomenon is due to the simultaneous activation of neurons spread in different cortical areas for a given specific movement, whilst the other neurons of the same areas connected with peripheral nerves of different muscles are not activated at the same time. Why different neurons of the same area fire at different times according to different voluntary demands remains to be discovered. We are committed to solve this enigma hereafter.

• Biomolecules & Therapeutics
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• 제19권3호
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• pp.315-319
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• 2011

Galanin (Gal) is a 29-amino-acid neuropeptide which is expressed in superior cervical ganglion (SCG) neurons and plays a trophic role in the adult animal and acts as an inhibitory modulator of cholinergic and noradrenergic neurotransmission. Whether activation or inhibition of alpha-adrenoreceptors infl uences Gal mRNA expression in SCG neurons remains unknown. Here, we have evaluated the possible regulation of Gal mRNA expression with acute (4 h) and chronic (4 days) stimulation of alpha 1- and alpha 2-adrenoreceptor agonists or antagonists in primary cultured SCG neurons. The results showed that the amount of Gal mRNA expression in cultured SCG neurons increased signifi cantly after chronic stimulation with alpha 2-adrenoreceptor antagonist yohimbine compared with control SCG neurons at the same time point, whereas the amount of Gal mRNA expression decreased signifi cantly after chronic stimulation with alpha 2-adrenoreceptor agonist clonidine as compared with that in control group. All these effects were not dose-dependent on the administration of alpha 2-adrenoreceptor agonist clonidine or alpha 2-adrenoreceptor antagonist yohimbine. Alpha 1-adrenoreceptor agonist phenylephrine or antagonist prazosin chronic stimulation did not have effects on Gal mRNA expression. Acute exposure of these agents did not have effects on Gal mRNA expression. The present study showed that Gal may be regulated by activation or inhibition of alpha 2-adrenoreceptors, but not alpha 1-adrenoreceptors in sympathetic neurons.

• Archives of Pharmacal Research
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• 제18권2호
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• pp.121-128
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• 1995

The role of nitric oxide (NO) in non-adrenegic non-cholinergic (NANC) neurotransmission was studied on circular muscle strips of the dorsal part of the fuinea-pig gastric fundus. In the presence of atropine and guanethidine, a low frequency-dependent relaxsations which were not affected by adrenergic and cholinergic blockage but abolished by tetrodotoxin. $N^G$-nitro-L-arginine (L-NNA), a stereospecific inhibitor of NO-biosynthesis, inhibited the relaxations induced by electrical stiumulations but not the relaxations to exogenous nitric oxide. The effect of L-NNA was prevented by L-arginine, the precursor of the NO biosynthesis but not by its enantiomer, D-arginine. Exgenous administration of No caused concentration -dependent relaxations which showed a similarity to those obtained with electrical simultaion. Hemoglobin, a NOscavenger, abolished the NO-induced relaxations and also markedly reduced those induced by electrical simultaion. The inhibitory effect os hemoglobin was similar to that of L-NNA. Application of ATP caused weak relaxations compared with those to electrical stimultaion, which were unaffected by L-NNA. Exogenously applied vasoactive intestinal polypeptide (VIP) induced concentration-dependent relaxation which was not affected by L-NNA. These results suggest that NO is produced and released mainly as a neurotransmitter from enteric neurons during NANC relaxation induced by low frequencies and short trains of electrical simulation and has a main role in NANC neurotransmission at relaxation induced by these electrical simultaions in the guinea-pig gastric fundus.

• Biomolecules & Therapeutics
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• 제24권3호
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• pp.328-337
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• 2016

We examined whether wogonin (WO) improved hippocampal neuronal activity, behavioral alterations and cognitive impairment, in rats induced by administration of trimethyltin (TMT), an organotin compound that is neurotoxic to these animals. The ability of WO to improve cognitive efficacy in the TMT-induced neurodegenerative rats was investigated using a passive avoidance test, and the Morris water maze test, and using immunohistochemistry to detect components of the acetylcholinergic system, brain-derived neurotrophic factor (BDNF), and cAMP-response element-binding protein (CREB) expression. Rats injected with TMT showed impairments in learning and memory and daily administration of WO improved memory function, and reduced aggressive behavior. Administration of WO significantly alleviated the TMT-induced loss of cholinergic immunoreactivity and restored the hippocampal expression levels of BDNF and CREB proteins and their encoding mRNAs to normal levels. These findings suggest that WO might be useful as a new therapy for treatment of various neurodegenerative diseases.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.259.3-260
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• 2003

Alzheimer's disease(AD) is the most common cause of senile dementia in elderly people and the causes of AD are currently not fully understood. However, AD is generally understood to be associated with reduced levels of acetylcholine in the brain as cholinergic neurons are lost and cholinergic neurotransmission declines. There are growing evidences that two types of cholinesterase(ChE), i.e., acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) both play important roles in the regulation of acetylcholine level in brain and thus may have a crucial role in the development and progression of AD. (omitted)

• The Korean Journal of Physiology and Pharmacology
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• 제16권2호
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• pp.79-89
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• 2012

We examine whether Phellodendron amurense (PA) and its major alkaloid compound, berberine (BER), improved memory defects caused by administering scopolamine in rats. Effects of PA and BER on the acetylcholinergic system and pro-inflammatory cytokines in the hippocampus were also investigated. Male rats were administered daily doses for 14 days of PA (100 and 200 mg/kg, i.p.) and BER (20 mg/kg, i.p.) 30 min before scopolamine injection (2 mg/kg, i.p.). Daily administration of PA and BER improved memory impairment as measured by the passive avoidance test and reduced the escape latency for finding the platform in the Morris water maze test. Administration of PA and BER significantly alleviated memory-associated decreases in cholinergic immunoreactivity and restored brain-derived neurotrophic factor and cAMP-response element-binding protein mRNA expression in the hippocampus. PA and BER also decreased significantly the expression of proinflammatory cytokines such as interleukin-$1{\beta}$, tumor necrosis factor-${\alpha}$ and cyclooxygenase-2 mRNA in the hippocampus. These results demonstrated that PA and BER had significant neuroprotective effects against neuronal impairment and memory dysfunction caused by scopolamine in rats. These results suggest that PA and BER may be useful as therapeutic agents for improving cognitive functioning by stimulating cholinergic enzyme activity and alleviating inflammatory responses.