• The Korean Journal of Physiology and Pharmacology
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• v.17 no.4
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• pp.331-338
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• 2013

AMP-activated protein kinase (AMPK), an important regulator of energy metabolism, is activated in response to cellular stress when intracellular levels of AMP increase. We investigated the neuroprotective effects of AMPK against scopolamine-induced memory impairment in vivo and glutamate-induced cytotoxicity in vitro. An adenovirus expressing AMPK wild type alpha subunit (WT) or a dominant negative form (DN) was injected into the hippocampus of rats using a stereotaxic apparatus. The AMPK WT-injected rats showed significant reversal of the scopolamine induced cognitive deficit as evaluated by escape latency in the Morris water maze. In addition, they showed enhanced acetylcholinesterase (AChE)-reactive neurons in the hippocampus, implying increased cholinergic activity in response to AMPK. We also studied the cellular mechanism by which AMPK protects against glutamate-induced cell death in primary cultured rat hippocampal neurons. We further demonstrated that AMPK WT-infected cells increased cell viability and reduced Annexin V positive hippocampal neurons. Western blot analysis indicated that AMPK WT-infected cells reduced the expression of Bax and had no effects on Bcl-2, which resulted in a decreased Bax/Bcl-2 ratio. These data suggest that AMPK is a useful cognitive impairment treatment target, and that its beneficial effects are mediated via the protective capacity of hippocampal neurons.

• Korean journal of applied entomology
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• v.34 no.2
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• pp.89-94
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• 1995

Resistance mechanism of organophosphorus insecticides (OPs) in the spiraea aphid, whose populations were originated from several apple orchards where various OPs were frequently sprayed, was investigated. For Wonju population to which insecticides were not sprayed, resistance ratios (BRs) for pirimicarb, phosphamidon, and demeton S-methyl re 49, 31, and 5, respectively. However, for Yesan population to which OPs were sprayed 5 times, RRs for pirimicarb, phosphamidn, and dementon were 830, 536, and 204, respectively. The esterase activities of Wonju and Yesean populations increased by 44.5 and 92.0% compare to that of Kwagju population. R/S a values (S clone Kwangju population; R clone: Iechon opulation) for acetylcholinesterase (AChE) inhibition (${I}_{50}$) by pirimicarb and phosphamidon were 299.2 and 186.0, respectively. Our results indicate that increase of esterase activity and reduction of AChE sensitivity seemed to contribute insecticide resistance of the spiraea aphid.

• Toxicological Research
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• v.24 no.2
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• pp.137-150
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• 2008

Sexually mature male and female rats were orally intubated with the organophosphorus insecticide, Pestban at a daily dosage of 7.45 or 3.72 mg/kg bwt, equivalent to 1/20 and 1/40 $LD_{50}$, respectively. Male rats were exposed for 70 days, while the female rats were exposed for 14 days, premating, during mating and throughout the whole length of gestation and lactation periods till weaning. The results showed depressed acetylcholinesterase(AChE) activity in the brain of parents, fetuses and their placentae in a dose-dependent manner. The fertility was significantly reduced with increasing the dose in both treated groups, with more pronounced suppressive effects in the male treated group. The number of implantation sites and viable fetuses were significantly reduced in pregnant females of both treated groups. However, the number of resorptions, dead fetuses, and pre-and postimplantation losses were significantly increased. The incidence of resorptions was more pronounced in treated female compared to male group and was dose dependant. The behavioral responses as well as fetal survival and viability indices were altered in both treated groups during the lactation period. The incidence of these effects was more pronounced in the treated female group and occurred in a dose-related manner. The recorded morphological, visceral, and skeletal anomalies were significantly increased with increasing the dose in fetuses of both treated groups, with more pronounced effects on fetuses of treated females. In conclusion, the exposure of adult male and female rats to Pestban would cause adverse effects on fertility and reproduction.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.6 no.2
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• pp.202-207
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• 2003

Intestinal neuronal dysplasia (IND) is a disorder of abnormal intestinal innervation resulting in dysfunctional colonic motility. IND shares clinical features with Hirschsprung's disease but differentiated by histological findings such as hyperplasia of submucosal and myenteric plexuses, giant ganglia, ectopic ganglion cell and increased acetylcholinesterase activity in lamina propria. Although IND may exist as an isolated condition, more commonly, it occurs in association with Hirschsprung's disease. We report a case of twins affected with IND. Both children manifested with delayed passage of meconium and severe abdominal distention after birth. Barium enema in both patients showed microcolon. They underwent emergency ileostomy under the impression of total aganglionosis. But surgical biopsy specimens showed hyperganglionosis in submucosa with formation of giant ganglia. Both neonates suffers from several episodes of peudo-obstruction after the repair operation of colostomy.

• Journal of Life Science
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• v.10 no.6
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• pp.564-569
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• 2000

This study was designed to investigate the effect of silkworm (Bombyx mori L.) powder on lipofuscin, acetylcholine (ACh) and its related enzyme activities in brain of rats. Sprague-Dawley (SD) male rats ($160{\pm}10g$) were fed basic diet (control group), and experimental diets (SWP-200 and SWP-400 groups) added 200 and 400 mg/kg BW/day for 6 weeks. In case of liver membranes, lipofuscin (LF) levels resulted in a slight decreases (4.6% and 11.5%, respectively) in SWP-200 and SWP-400 groups compared with control group. But in case of barin as the most sensitive organ, LF levels were remarkably inhibited about 16.7% and 20.0% in SWP-200 and SWP-400 groups compared with control group. There were no significant differences in acetylcholine (ACh) syntheses as a very important neurotransmitter, and choline acetyltransferase (ChAT) activities as a synthesis enzyme of ACh, and acetylcholinesterase (AChE) activities as a hydrolysis enzyme, which were concerned in transmission of neuron through synapses in brain of SWP-200 and SWP-400 groups compared with control group. Monoamine oxidase-B (MAO-B) activities were significantly inhibited (about 10.2%) in brain of SWP-400 groups compared with control group. These results suggest that inhibiting effects of LF accumulation and MAO-B activity of silkworm powder (SWP) may play a pivotal role in attenuating a various age-related changes for improvement of brain function.

• Journal of Sericultural and Entomological Science
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• v.42 no.2
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• pp.120-125
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• 2000

This study was designed to investigate the effects of silk fibroin (Mw 500) powder (SFP) on lipofuscin, acetylcholine (ACh) and its related enzyme activities in brain of rats. Sprague-Dawley (SD) male rats (160$\pm$10 g) were fed basic diet (control group), and experimental diets (SFP-2.5 and SFp-5.0 groups) added 2.5 and 5.0 g/kg BW/day for 6 weeks. In case of liver membranes, lipofuscin (LF) levels resulted in a considerable decreases (11.5% and 13.8%, respectively) in SFP-2.5 and SFP-5.0 groups compared with control group. But in case of brain as the most sensitive organ, LF levels were remarkably inhibited about 18.3% and 21.7% in SFP-2.5 and SFP-5.0 groups compared with control group. Acetylcholine (ACh) levels were considerable decrease (3.0% and 9.2%, respectively) in brain membranes of SFP-2.5 and SFP-5.0 groups compared with control group. choine acetyltranferase (ChAT) activities as a synthesis enzyme of ACh, and acetylcholinesterase (AChE) activities as a hydrolysis enzyme resulted in a slight increases (2.4% and 3.0%, 4.6% and 6.3%, respectively), but significance difference between ChAT and AChE activities by SFP administration could be not obtained. Monoamine oxidase-B (MAO-B) activities were significantly inhibited (9.5% and 12.6%, respectively) in brain of SEP-2.5 and SFP-5.0 groups compared with control group. These results suggest that inhibiting effects of LF accumulation and MAO-B activity of silk fibroin(SFP) may play a pivotal role in protecting learning memory impairments by attenuating a various age-related changes for improvement of brain function.

• Korean Journal of Medicinal Crop Science
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• v.25 no.6
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• pp.353-360
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• 2017

Background: A critical features of Alzheimer's disease (AD) is cognitive dysfunction, which partly arises from decreased in acetylcholine levels. AD afftected brains are characterized by extensive oxidative stress, which is thought to be primarily induced by the amyloid beta ($A{\beta}$) peptide. In a previous study, Cinnamomum loureiroi tincture inhibited acetylcholinesterase (AchE) activity. That study identified AChE inhibitor in the C. loureiroi extract. Furthermore, the C. loureiroi extract enhanced memory in a trimethyltin (TMT)-induced model of cognitive dysfunction, as assessed via two behavioral tests. Rosa laevigata extract protected against oxidative stress-induced cytotoxicity. Administrating R. laevigata extracts to mice significantly reversed $A{\beta}$-induced learning and memory impairment, as shown in behavioral tests. Methods and Results: We conducted behavioral to examine the synergistic effects of C. loureiroi and R. laevigata extracts in inhibiting AChE and counteracting TMT-induced learning and memory losses. We also performed biochemical assays. The biochemical results showed a relationship between increased oxidative stress and cholinergic neurons damage in TMT-treated mice. Conclusions: A diet containing C. loureiroi and R. laevigata extracts ameliorated learning and memory impairments in the Y-maze and passive avoidance tests, and exerted synergistic inhibitory effect against AChE and lipid peroxidation.

• The Korean Journal of Physiology and Pharmacology
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• v.28 no.4
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• pp.361-377
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• 2024

The dried rattan stem of the Fibraurea Recisa Pierre plant contains the active ingredient known as fibrauretine (FN). Although it greatly affects Alzheimer's disease (AD), the mechanism of their effects still remains unclear. Proteomics and transcriptomics analysis methods were used in this study to determine the mechanism of FN in the treatment of AD. AD model is used through bilateral hippocampal injection of Aβ_1-40. After successful modeling, FN was given for 30 days. The results showed that FN could improve the cognitive dysfunction of AD model rats, reduce the expression of AE and P-Tau, increase the content of acetylcholine and reduce the activity of acetylcholinesterase. The Kyoto Encyclopedia of Genes and Genomes enriched differentially expressed genes and proteins are involved in signaling pathways including metabolic pathway, AD, pathway in cancer, PI3K-AKT signaling pathway, and cAMP signaling pathway. Transcriptomics and proteomics sequencing resulted in 19 differentially expressed genes and proteins. Finally, in contrast to the model group, after FN treatment, the protein expressions and genes associated with the PI3K-AKT pathway were significantly improved in RT-qPCR and Western blot and assays. This is consistent with the findings of transcriptomic and proteomic analyses. Our study found that, FN may improve some symptoms of AD model rats through PI3K-AKT signaling pathway.

• Korean Journal of Environmental Agriculture
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• v.14 no.2
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• pp.163-170
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• 1995

This study was carried out to compare the acute toxicity(96hr) of 13 chemicals to carp (Cyprinus carpio L.) and israeli carp (Cyprinus israeli carpio L.) and the activities of acetylcholinesterase (AchE) and glutathione S-transferase (GST) in israeli carp exposed to five insecticides (diazinon, malathion, carbofuran, cartap, methomyl). $LC_{50}$ values of acute toxicity of the chemicals to israeli carp were endosulfan 0.0061ppm, captafol 0.041ppm, chlorothalonil 0.073ppm, butachlor 0.48ppm, captan 0.14ppm, carbofuran 1.13ppm, cartap 1.15ppm, diazinon 1.35ppm, nitrofen 3.72ppm, methomyl 4.39ppm, propanil 10.61ppm, malathion 11.78ppm and isoprothiolane 12.81ppm. The acute toxicity of endosulfan 0.0061ppm was 2100 times higher than that of isoprothiolane 12.81ppm. $LC_{50}$ values of acute toxicity of the chemicals to carp were endosulfan 0.0026ppm, captafol 0.062ppm, chlorothalonil 0.078ppm, captan 0.14ppm, and butachlor 0.47ppm, carbofuran 0.52ppm, nitrofen 0.58ppm, diazinon 0.81ppm, cartap 0.82ppm, methomyl 5.03ppm, propanil 10.67ppm, malathion 11.92ppm, and isoprothiolane 13.20ppm. The acute toxicity of endosulfan was 5,000 times higher than that of isoprothiolane. The toxicity of diazinon, carbofuran, cartap, endosulfan, and nitrofen to carp was approximately 2-6 times as high as that to israeli carp, but the toxicity of malathion, methomyl and captafol to israeli carp was slightly higher than that to carp. AchE activity was inhibited by 31% and 52% after 96hr’s exposure of israeli carp to diazinon and malathion respectively. GST activity in israeli carp was significantly induced by methomyl exposure for 96 hr.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.614-619
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• 1997

This study was designed to investigate the biochemical pollutant markers for diagnosis of marine pollutions by changes in cholinesterase activity of the flounder (Pleuronichthys cornutus) in the Yellow Sea of Korea. Acetylchotinesterase (AChE) activities in brain and muscle of wild flounders in the Yellow Sea were significantly lower $(20\~30\%\;and\;10\~40\%,\;respectively)$ than those of wild flounder in Pohang (control) of the last Sea. Butyrylcholinesterase (BChE) activities in brain and muscle of wild flounders in the Yellow Sea were significantly lower $(10\~30\%\;and\;35\~45\%,\;respectively)$ than those of wild flounder in Pohang of the East Sea. lactate dehydrogenase (LDH) activities in serum of wild flounders in the yellow Sea were significantly $(about\;30\%)$ lower than those of wild flounder in Pohang of the East Sea. These results suggest that AChE and BChE activities in brain and muscle of wild flounders of the Yellow Sea may be used as the most effective mean in a biochemical marker for diagnosis of pollutant effects by organophosphorus pesticides.