• Korean Journal of Pharmacognosy
• /
• v.38 no.1
• /
• pp.27-30
• /
• 2007

We examined the inhibitory activities against monoamine oxidase (MAO) of Chrysanthemum indicum L. in vitro and in vivo methods. Methanolic extract of C. indicum showed significant inhibitory activities on MAO-A that were prepared from rat brain in vitro. The inhibitory activities were measured by serotonin as a substrate. The $IC_{50}$ value of methanolic extract of C. indicum was 0.24 mg/ml for the inhibition of MAO-A. The ethylacetate fraction of methanolic extract of C. indicum exhibited the best activity toward MAO-A with $IC_{50}$ value of 0.05 mg/ml in vitro. It was observed that those activities in vivo tests have different tendency each other. Ethanolic extract of C. indicum was have no effect on rat MAO by the oral administration (p<0.05). However, MAO inhibitory activities of ethanolic extract of C. indicum by the oral administration have similar tendency to those of iproniazid. Consequently, we suggest that C. indicum may have the effects on the inhibitory activities against MAO both in vitro and in vivo. These results indicates that the C. indicum extract has properties indicative of potential neuroprotective ability.

• KSBB Journal
• /
• v.29 no.4
• /
• pp.244-249
• /
• 2014

Biosynthesis pathway of medium-chain-length (MCL) polyhydroxyalkanoates (PHA) from fatty acid ${\beta}$-oxidation pathway was constructed in recombinant Escherichia coli by introducing the Pseudomonas sp. 61-3 PHA synthase gene (phaC2) and the maoC genes from Pseudomonas putida, Sinorhizobium meliloti, and Ralstonia eutropha. The metabolic link between fatty acid ${\beta}$-oxidation pathway and PHA biosynthesis pathway was constructed by MaoC, which is homologous to P. aeruginosa (R)-specific enoyl-CoA hydratase (PhaJ1). When the E. coli W3110 strains expressing the phaC2 gene and one of the maoC genes from P. putida, Sinorhizobium meliloti, and Ralstonia eutropha were cultured in LB medium containing 2 g/L of sodium decanoate as a carbon source, MCL-PHA that mainly consists of 3-hydroxyhexanoate (3HHx), 3-hydroxyoctanoate (3HO) and 3-hydroxydecanoate (3HD), was produced. The monomer composition of PHA and PHA contents varied depending on MaoC employed for the production of PHA. The highest PHA content of 18.7 wt% was achieved in recombinant E. coli W3110 expressing the phaC2 gene and the P. putida maoC gene. These results suggest that MCL-PHA biosynthesis pathway can be constructed in recombinant E. coli strains from the b-oxidation pathway by employing MaoC able to supply (R)-3-hydroxyacyl-CoA, the substrate of PHA synthase.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.9
• /
• pp.1425-1428
• /
• 2015

Monoamine oxidase (MAO) is found in most cell types and catalyzes the oxidation of monoamines. Three anithiactins (A-C, modified 2-phenylthiazoles) isolated from Streptomyces sp. were tested for inhibitory activity of two isoforms, MAO-A and MAO-B. Anithiactin A was effective and selective for the inhibition of MAO-A, with an IC₅₀ value of 13.0 μM; however, it was not effective for the inhibition of MAO-B. Anithiactins B and C were weaker inhibitors for MAO-A and MAO-B. Anithiactin A was a reversible and competitive inhibitor for MAO-A with a K_i value of 1.84 μM. The hydrophobic methyl substituent in anithiactin A may play an important role in the inhibition of MAO-A. It is suggested that anithiactin A is a selective reversible inhibitor for MAO-A, with moderate potency, and can be considered a new potential lead compound for further development of novel reversible inhibitors for MAO-A.

• Radiation Oncology Journal
• /
• v.11 no.2
• /
• pp.205-217
• /
• 1993

In order to evalute the effects of radiation on mammalian neuronal system, we have examined the effect of gamma-ray radiation on the monoamine oxidase (MAO) activity in monoaminergic neurons. Following the whole body irradiation, MAO activity in the rat brain was measured as well as in the liver for the comparative studies between the neuronal and nonneuronal system. The effects of some radiation protectors and sensitizers were also examined in addition to the $O_2$ effect. The results can be summarized as follows. 1) The MAO activity of rat brain was minimally affected by the radiation dose up to 1,700 cGy Radiation dose above 2,500 cGy inhibited the brain MAO activity by no less than $l0\%.$ MAO-A form was found to be particularly sensitive to radiation. The liver MAO was somewhat inhibited (by about $5\%$) but hardly dependent on the dose of radiation. 2) The inhibitory effect on the brain was initiated immediately by the radiation dose of 2,500 cGy. On the contrary, for the liver, the inhibitory effect became apparent only 2 days after irradiation. 3) Two days after a dose of 2,500 cGy, Vmax and Km of the brain mitochondrial MAO decreased. For liver, Vmax decreased while Km increased, which indicates the kinetic patterns for the neuronal and nonneruronal systems are not affected similarly by radiation. 4) The effect of several known radiation protectors and sensitizers on MAO activity was tested ut no definite results were obtained. The level of -SH group increased in some degree upon radiation but not by the compounds. 5) MAO activity was not affected by $O_2$ concentration, while an elevated level of lipid peroxidase was found under the same condition. The results described here indicate that characteristics of MAO, one of the most important central nervous system enzymes, are liable to radiation, which is partially differentiated from the liver MAO. Also indicated are that the -SH groups are hardly related to the effect of radiation but the production of the lipid peroxide seems to be somewhat correlated to the effect of radiation.

• The Korean Journal of Physiology and Pharmacology
• /
• v.10 no.4
• /
• pp.207-212
• /
• 2006

Mitochondrial permeability transition has been shown to be involved in neuronal cell death. Mitochondrial monoamine oxidase (MAO)-B is considered to play a part in the progress of nigrostriatal cell death. The present study examined the effect of MAO inhibitors against the toxicity of 1-methyl-4-phenylpyridinium $(MPP^+)$ in relation to the mitochondrial permeability transition. Chlorgyline (a selective inhibitor of MAO-A), deprenyl (a selective inhibitor of MAO-B) and tranylcypromine (nonselective inhibitor of MAO) all prevented cell viability loss, cytochrome c release, caspase-3 activation, formation of reactive oxygen species and depletion of GSH in differentiated PC12 cells treated with $500\;{\mu}M$$MPP^+$. The MAO inhibitors at $10\;{\mu}M$ revealed a maximal inhibitory effect and beyond this concentration the inhibitory effect declined. On the basis of concentration, the inhibitory potency was tranylcypromine, deprenyl and chlorgyline order. The results suggest that chlorgyline, deprenyl and tranylcypromine attenuate the toxicity of $MPP^+$ against PC12 cells by suppressing the mitochondrial permeability transition that seems to be mediated by oxidative stress.

• The Korean Journal of Zoology
• /
• v.38 no.4
• /
• pp.498-504
• /
• 1995

The effeds of riboflavin defidency on the biosynthesis of flavin pepddes and levels of flavoenzymes and catecholamines have been investigated. The percentage of 14C. riboflavin radioactivity formed in mitochondria appeared to increase up to 2 weeks but started to decline at 3 weeks. A significant increase of radioactivity incorporation into mitochondria and into trypsin-digestable plus trypsin-non-digestibie flavin peptides was detected in riboflavin-deficient animals. More than 35% of incorporation was observed at the end of the first week and 160% higher incorporation was observed in fiavin peptide after the second week. Activities of MAO and succinate dehydrogenase were affected markedly by riboflavin status whereas those of acetyichoilnesterase were not affected. Riboflavin defidency also brought about marked reductions in levels of epineplrrine and norepinephrine. it is concluded that the levels of flavin peptides, MAO and succinate dehydrogenase, and catecholamines were affected significanily by the availability of riboflavin and in particular the duration of its depiction.

• Analytical Science and Technology
• /
• v.9 no.2
• /
• pp.203-209
• /
• 1996

Kaminsky catalyst system($Et(Ind)_2ZrCl_2$ and MAO(methylaluminoxane)) was prepared. Propylene was polymerized at $60^{\circ}C$ in this system. The microstructure was studied by using the $^{13}C$ NMR spectrometer. From the $^{13}C$ NMR data, the 2, 1-insertion of propylene was controlled stereospecific by Kaminsky catalyst due to the structures of meso and racemo I. After the 2, 1-insertion of propylene, 1, 2-insertion of the chain end was less stereospecifically controlled by the catalyst.

• Polymer(Korea)
• /
• v.28 no.3
• /
• pp.281-284
• /
• 2004

비닐 형태의 부가중합에 의해 생성된 비결정 폴리노보넨은 주사슬이 고리화합물로 이루어져 있으며, 높은 고체밀도와 유리 전이 온도를 나타내며, 낮은 유전상수를 가지는 특징이 있다. 광학적으로 폴리노보넨은 낮은 투과손실을 가지고 있는데, 광통신 대역인 850 nm에서 삽입 손실이 0.1 dB/cm이고, 복굴절이 0.001을 나타내어 광결합 소자 및 광소자에 응용이 기대된다. 이는 주사슬의 고리화합물에 의해 결정화되지 않아, 유리 전이 온도가 28$0^{\circ}C$로 높으면서 비결정의 투명성을 가지기 때문이다.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1998.11a
• /
• pp.132-132
• /
• 1998

It has been known that MAO (monoamine oxidase) catalyses the oxidation of endogenous neurotransmitter amines. From its key role in the regulation of some physiological amines, it has been the target of inhibitors used as antidepressive agents. In our continuing search for MAO inhibitors from Basidiomycete. sp., strain 8082 was selected. Two metabolites (8082-1 and 8082-2) were isolated by adsorption chromatography and HPLC from the culture broth of strain 8082. The structure of 8082-1 and 8082-2 were elucidated by $^1$H-, $\^$13/C-NMR and HMBC spectral data, and these products were identified as 5-methylmellein and nectriapyrone, respectively, which have significant inhibitory effect against mouse brain MAO.

• YAKHAK HOEJI
• /
• v.46 no.6
• /
• pp.433-440
• /
• 2002

The protective efficacy of Rheum palmatum water extract on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced parkinsonism was studied in C57BL/6 mice. In order to demonstrate neuroprotective effect of R. palmatum extract, animals were administered intraperitoneally with the water extract (100 or 200 mg/kg/day) for 14 days, and MPTP (10 mg/kg/day) was injected subcutaneously into the mice for the first 6 consecutive days from the beginning 1 hr before R. palmatum extract treatment. All animals were measured the several neurobiochemical markers such as dopamine level and monoamine oxidase B (MAO-B) activity in various regions of brain. The treatment of mice with R. palmatum extract was confirmed recovery effect on MAO-B activity in the cerebellum and the cerebral cortex. R. palmatum extract was attenuated the MPTP-induced depletion of substantia nigra dopamine. The contents of MDA, a marker of lipid peroxidation, in brain tissues (cerebellum and cerebral cortex mitochondria) were decreased significantly by R. palmatum extract. These results suggest that R. palmatum water extract plays an effective role in attenuating MPTP-induced neurotoxicity in mice. This protective effect of R. palmatum might be estimated the result from the inhibitory activity on monoamine oxidase B and the enhancement of antioxidant activity.