• Korean Journal of Pharmacognosy
• /
• v.47 no.3
• /
• pp.287-294
• /
• 2016

Acetylcholinesterase (AChE) activation and amyloid-${\beta}$ ($A{\beta}$) aggregation are major biological markers of Alzheimer's disease. In the present study, we evaluated the inhibitory effects of 50 kinds of herbal formulas on AChE activity and $A{\beta}$ aggregation. Among them, Hwanglyeonhaedok-tang, Cheonwangbosim-dan, Makmundong-tang, and Gamisoyo-san had a potent effects on the inhbition of AChE activity. Sosiho-tang, Samsoeum, Cheonsimyeunjaeum, and Bunsimgieum exerted to have the inhibitory activity on $A{\beta}$ aggregation. In addition, these 8 herbal formulas showed the 3-ethyl-benzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity, indicating their antioxidant activities.

• Food Science and Biotechnology
• /
• v.18 no.6
• /
• pp.1532-1536
• /
• 2009

The objective of this study was to evaluate the antioxidant effects and acetylcholinesterase (AChE) inhibition activity of mulberry fruit extracts prepared by hot water (MFH) and 80% ethanol (MFE). Total polyphenolic contents of MFH and MFE were $195{\pm}3.4\;mg$ gallic acid equivalents/g MFH and $185{\pm}2.8\;mg$ gallic acid equivalents/g MFE. MFH and MFE significantly quenched 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydrogen peroxide dose-dependently, and showed high chelating ability and reducing power in non-cellular systems. MFH and MFE also inhibited the formation of intracellular reactive oxygen species and lipid peroxidation, and elevated intracellular glutathione (GSH) levels in RAW264.7 cells. In addition, MFH and MFE also dose-dependently suppressed AChE activity.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.6
• /
• pp.1609-1614
• /
• 2010

Acetylcholinesterase reactivators are crucial antidotes for the treatment of organophosphate intoxication. Standard in vitro test was chosen using a rat brain homogenate as the source of AChE. Screening of reactivation potency was performed with two concentration of reactivator (1000 ${\mu}M$ and 10 ${\mu}M$). Results were compared to established reactivators pralidoxime, methoxime, HI-6, trimedoxime and obidoxime. More than 30 novel reactivators performed equal or better reactivation ability of POX-inhibited AChE compared to currently used reactivators. The structure-activity relationship for reactivators of paraoxon-inhibited AChE was developed.

• Archives of Pharmacal Research
• /
• v.27 no.1
• /
• pp.53-56
• /
• 2004

In the course of finding Korean natural products with acetylcholinesterase (AChE) inhibitory activity, we found that a methanolic extract of the twigs of Vaccinium oldhami significantly inhibited AChE. Bioassay-guided fractionation of the methanolic extract resulted in the isolation of two compounds, taraxerol (1) and scopoletin (2), as active constituents. These compounds inhibited AChE activity in a dose-dependent manner, and the $IC_{50}$/ values of compounds 1 and 2 were 33.6 (79 $\muM$) and 10.0 (52 $\muM$) $\mu$g/mL, respectively.

• Journal of Microbiology and Biotechnology
• /
• v.23 no.2
• /
• pp.161-166
• /
• 2013

At present, acetylcholinesterase (AChE) inhibitors are the first group of drugs to treat mild to moderate Alzheimer's disease (AD). Although beneficial in improving cognitive and behavioral symptoms, the effectiveness of AChE inhibitors has been questioned since they do not delay or prevent neurodegeneration in AD patients. Therefore, in the present study, in order to develop new and effective anti-AD agents from lichen products, both the AChE inhibitory and the neuroprotective effects were evaluated. The AChE inhibitory assay was performed based on Ellman's reaction, and the neuroprotective effect was evaluated by using the MTT method on injured PC12 cells. One AChE inhibitor ($IC_{50}$ = 27.1 ${\mu}g/ml$) was isolated by means of bioactivity-guided isolation from the extract of lichen-forming fungus Cladonia macilenta, which showed the most potent AChE inhibitory activity in previous screening experiment. It was then identified as biruloquinone by MS, and $^1H$- and $^{13}C$-NMR analyses. The inhibitory kinetic assay suggested that biruloquinone is a mixed-II inhibitor on AChE. Meanwhile, biruloquinone improved the viability of the $H_2O_2$- and ${\beta}$-amyloid-injured PC12 cells at 1 to 25 ${\mu}g/ml$. The protective effects are proposed to be related to the potent antioxidant activities of biruloquinone. These results imply that biruloquinone has the potential to be developed as a multifunctional anti- AD agent.

• BMB Reports
• /
• v.31 no.3
• /
• pp.296-302
• /
• 1998

A potentiometric flow injection biosensor for the analysis of anti-cholinesterases (anti-ChEs), based on inhibition of enzyme activity, was developed. The sensor system consists of a reactor with acetylcholinesterase (AChE) immobilized on controlled pore glass and a detector with an $H^{+}-selective$ PVC-based membrane electrode. The principle of the analysis is based on the fact that the degree of inhibition of AChE by an anti-ChE is dependent on the concentration of the anti-ChE in contact with AChE. The sensor system was optimized by changing systematically the operating parameters of the sensor to evaluate the effect of the changes on sensor response to ACh. The optimized biosensor was applied to the analysis of paraoxon, an organophosphorus pesticide. Treatment of the inhibited enzyme with pyridine-2-aldoxime fully restored the enzyme activity allowing repeated use of the sensor.

• Applied Biological Chemistry
• /
• v.29 no.3
• /
• pp.324-330
• /
• 1986

The responses of brain acetylcholinesterase(Ach-E) and plasma cholinesterase (Ch-E) activities were studied in chicknes given oral doses of Terbufos(S-tert-butyl thiomethyl 0,0-diethyl phosphorodithioate), an organophosphorus insecticide. The acute oral $LD_{50}$ of terbufos was 1.82mg/kg. The activity of plasma Ch-E was inhibited more rapidly than that of brain Ach-E, whereas recovery of plasma Ch-E activity was more rapid than that of brain Ach-E. Recovery of brain Ach-E and plasma Ch-E was followed the model $Y=a+b(log_{10}X)$. Brain Ach-E activity and plasma Ch-E were inhibited 83% and 94%, respectively, at 60min after administered oral $LD_{50}$. Brain Ach-E and plasma Ch-E was inhibited in vitro by Terbufos

• Journal of The Korean Society of Clinical Toxicology
• /
• v.6 no.1
• /
• pp.25-31
• /
• 2008

Purpose: Acute organophosphate (OP) poisoning may be monitored by measuring the acetylcholinesterase (AChE). It is important to assess severity and establish prognostic tests in the early stage of OP poisoning. The aim of this study was to look at the relationship between various clinical aspects of the OP poisoning, prognostic indicators of OP poisoning including Simplified Acute Physiology Score (SAPS) 3, and the associated changes in AChE levels. Methods: Clinical data and initial AChE levels from thirty-seven patients with OP poisoning were prospectively reviewed from 12 teaching hospitals in South Korea from August 2005 to July 2006. Clinical manifestations at the time of arrival such as miosis, respiratory abnormality, salivation, urinary incontinence, GCS score, AVPU scale, need for intubation, and mechanical ventilation requirements were recorded. SAPS 3 was calculated using clinical data and laboratory results. Results: The median level of AChE was 9.8 (1.3-53.6) U/gHb. There was no significant difference in AChE levels between the groups with and without cholinergic symptoms. The median level of AChE of the patients who required intubation and those who did not were 3.5 U/gHb and it 19.7 U/gHb respectively (Mann-Whitney test; p<0.001). The AChE levels were also significantly different (p=0.007) in patients who needed mechanical ventilation compared to those who did not with AChE levels found to be 3.1 U/gHb and it was 14.8 U/gHb, respectively. Level of consciousness assessed using the AVPU scale was correlated with AChE levels (Kruskal-Wallis test; p=0.013). GCS score were correlated with AChE levels (p=0.007, Spearman's rho = 0.454). In addition, the lower the level of initial AChE, the longer the ICU stay (p=0.029, Spearman's rho=-0.380). SAPS 3 was inversely correlated with the initial AChE (p<0.001, Spearman's rho=-0.633). Conclusion: In the acute OP poisoning, low AChE levels appear to help indicate the severity of poisoning. The initial AChE level may be a useful prognostic parameter for acute OP poisoning.

• Korean Journal of Plant Resources
• /
• v.32 no.4
• /
• pp.270-274
• /
• 2019

Anti-acetylcholinesterase (anti-AChE) activity and peroxynitrite scavenging activity of Ainsliaea acerifolia (Compositae) were studied to find its anti-Alzheimer's activity. The $IC_{50}$ was $73.4{\mu}g/mL$ in AChE assay and $8.60{\mu}g/mL$ in peroxynitrite assay. Caffeoylquinic acids that have been reported to have anti-Alzheimer's activity were analyzed in the leaf- and stem extract by HPLC. Caffeoylquinic acids occupied 25.1% of the leaf extract which was higher than 8.1% of the stem extract. Particularly, the content of 3,5-dicaffeoylquinic acid (145.6 mg/g) was highest of the tested caffeoylquinic acids. In addition, the $IC_{50}$ values of 3,5-dicaffeoylquinic acid were shown to be $3.79{\mu}g/mL$ in peroxynitrite assay and $69.19{\mu}g/mL$ in anti-AChE assay.

• Korean Journal of Food Science and Technology
• /
• v.41 no.4
• /
• pp.435-440
• /
• 2009

Acetylcholinesterase (AChE) inhibitors, which enhance cholinergic transmission by reducing the enzymatic degradation of acetylcholine, are the only source of the compound that is currently approved for the treatment of Alzheimer's disease (AD). In these experiments, the concentration samples of green tea extracts were 100, 500, and 1,000 ${\mu}g$/mL. Among them, the highest concentration (1,000 ${\mu}g$/mL) of fresh green tea extracts showed the most potent inhibitory effect on AChE by reducing more than 40% of enzyme activity, and in a concentration-dependent pattern. In addition, we examined the effect of other storing conditions on AChE inhibition. In order to maintain storage for 3 months, the materials were held at the certain storing conditions of temperature (room temperature, 4 and $-20^{\circ}C$) and for water activity (0.81, 0.69, and 0.23). In these storing conditions, the difference in temperature did not contribute to the AChE inhibitory effect. Our presented data showed that the AChE inhibitory effect was affected by the concentration of green tea extract and by water activity (0.81). These results suggest that green tea may serve as a potential dietary source of AChE inhibitor.