• International Journal of Oral Biology
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• v.35 no.4
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• pp.169-175
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• 2010

Cholinesterase (ChE) is one of the most ubiquitous enzymes and in addition to its well characterized catalytic function, the morphogenetic involvement of ChE has also been demonstrated in neuronal tissues and in non-neuronal tissues such as bone and cartilage. We have previously reported that during mouse tooth development, acetylcholinesterase (AChE) activity is dynamically localized in the dental epithelium and its derivatives whereas butyrylcholinesterase (BuChE) activity is localized in the dental follicles. To test the functional conservation of ChE in tooth morphogenesis among different species, we performed cholinesterase histochemistry following the use of specific inhibitors of developing molar and incisors in the hamster from embryonic day 11 (E11) to postnatal day 1 (P1). In the developing molar in hamster, the localization of ChE activity was found to be very similar to that of the mouse. At the bud stage, no ChE activity was found in the tooth buds, but was first detectable in the dental epithelium and dental follicles at the cap and bell stages. AChE activity was found to be principally localized in the dental epithelium whereas BuChE activity was observed in the dental follicle. In contrast to the ChE activity in the molars, BuChE activity was specifically observed in the secretory ameloblasts of the incisors, whilst no AChE activity was found in the dental epithelium of incisors. The subtype and localization of ChE activity in the dental epithelium of the incisor thus differed from those of the molar in hamster. In addition, these patterns also differed from the ChE activity in the mouse incisor. These results strongly suggest that ChE may play roles in the differentiation of the dental epithelium and dental follicle in hamster, and that morphogenetic subtypes of ChE may be variable among species and tooth types.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.190.2-190.2
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• 2003

In the course of search for various bioactive compounds from marine algae, we found strong antioxidant activity of the methanolic extract of the brown alga G. elliptica. Chromatographic purification [ODS flash, gel-filtration on Sephadex LH-20, HPLC] of the BuOH layer of the methanolic extract afforded two known polyphenolic compounds, 6,6'-bieckol (1) and dieckol (2). Compound 1 showed acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activities, free radical scavenging activity on DPPH (1,1-diphenyl-2-picryl-hydazyl) with IC$\_$50/ values of 91.2, 45.6 and 15.5 $\mu\textrm{g}$/$m\ell$, respectively. (omitted)

• Ocean and Polar Research
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• v.39 no.1
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• pp.45-49
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• 2017

During the search for anticholinesterase compounds from marine organisms, we were able to isolate 6,6'-bieckol from a red alga, Grateloupia elliptica. This compound showed moderate acetylcholinesterase (AChE) inhibitory activity in a micromole range ($IC_{50}$ $44.5{\mu}M$). However, for butyrylcholinesterase (BuChE), a new target for the treatment of Alzheimer's disease (AD), it showed particularly potent inhibitory activity ($IC_{50}$ $27.4{\mu}M$), which is more potent compared to AChE. It also inhibits BACE-1, a new target for reducing the generation of ${\beta}-amyloid$.

• Bulletin of the Korean Chemical Society
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• v.28 no.2
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• pp.225-228
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• 2007

Lipoic acid (LA) is a multifunctional antioxidant against a variety of ROS. Nitrone acts as free radical spin trap and exhibits neuroprotective activity. Thus, LA-nitrone derivatives (6, 7, 8, and 9) were synthesized and screened as an antioxidant and inhibitors for cholinesterases. Even though the antioxidant effect of LA-nitrone derivatives was not improved, they turned out to be effective inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in μM range.

• Fisheries and Aquatic Sciences
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• v.25 no.2
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• pp.49-63
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• 2022

Anti-cholinesterase (ChE)s are commonly prescribed as the symptomatic treatment of Alzheimer's disease. They are applied to prevent the breakdown of neurotransmitter acetylcholine (ACh) that bind to muscarinic and nicotinic receptors in the synaptic cleft. Seaweeds are one of the richest sources of bioactive compounds for both nutraceuticals and pharmacognosy applications. This study aimed to determine the anti-ChEs activity of Gracilaria manilaensis, one of the red seaweeds notables for its economic importance as food and raw materials for agar production. Methanol extracts (GMM) of G. manilaensis were prepared through maceration, and further purified with column chromatography into a semi-pure fraction. Ellman assay was carried out to determine the anti-acetylcholinesterase (AChE) and anti-butyrylcholinesterase (BuChE) activities of extracts and fractions. Lineweaver-Burk plot analysis was carried out to determine the inhibition kinetic of potent extract and fraction. Major compound(s) from the most potent fraction was determined by liquid chromatography-mass spectrometry (LCMS). GMM and fraction G (GMMG) showed significant inhibitory activity AChE with EC₅₀ of 2.6 mg/mL and 2.3 mg/mL respectively. GMM and GMMG exhibit mixed-inhibition and uncompetitive inhibition respectively against AChE. GMMG possesses neuroprotective compounds such as cynerine A, graveolinine, militarinone A, eplerenone and curumenol. These findings showed a promising insight of G. manilaensis to be served as a nutraceutical for neuronal health care in the future.

• Korean Journal of Plant Resources
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• v.31 no.5
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• pp.433-452
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• 2018

This study was conducted to select candidates from plant resources for the purpose of improving or treating Alzheimer's disease, a type of dementia. One hundred and eighty-four plant extracts at a final concentration of $100{\mu}g/ml$ were screened to determine their capacity to inhibit acetylcholinesterase (AChE) by in vitro assay. From this AChE assay, seven plant extracts - including methanol ext. and water ext. of Phellaodendron amurense Rupr. (bark), methanol ext. of Nelumbo nucifera Gaertn (stamen/ovary), methanol ext. of Persicaria tinctoria H. GROSS (flower), methanol ext. of Coptis chinensis (rhizome), ethanol ext. of Cinnamomum cassia Blume(bark) and ethanol ext. of Carthamus tinctorius L. (fruit) - showed effective inhibition activity ranging from 18.7% to 63.1%. The selected extracts were testified their inhibition activities on AChE and BuChE (butyrylcholinesterase) at concentrations of 25, 50, 100, $200{\mu}g/ml$. In the AChE assay, five extracts including methanol ext. of Nelumbo nucifera Gaertn. (stamen/ovary), methanol ext. of Persicaria tinctoria H. GROSS (flower), methanol ext. of Coptis chinensis (rhizome), methanol ext. and water ext. of Phellaodendron amurense Rupr. (bark) showed inhibition activity of 15.0%~73.5%, 19.5%~63.5%, 81.6%~58.5%, 69.9%~80.5%, and 54.8%~78.3%, respectively, at concentrations of 25, 50, 100, $200{\mu}g/ml$. In the BuChE assay, the extracts of Nelumbo nucifera Gaertn. (stamen/ovary), Persicaria tinctoria H. GROSS (flower), and Coptis chinensis (rhizome) showed inhibitory capacities of 58.9~81.6%, 45.8%~72.4%, and 33.1%~55.4% at concentrations of 25, 50, 100, $200{\mu}g/ml$, respectively. In conclusion, it is suggested that Nelumbo nucifera Gaertn. (stamen/ovary), Persicaria tinctoria H. GROSS, Coptis chinensis (rhizome) and Phellaodendron amurense Rupr. (bark) could be selected as candidate materials for improving or treating Alzheimer's disease on the basis of further study.