• Preventive Nutrition and Food Science
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• 제7권1호
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• pp.67-71
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• 2002

Capsaicin (trans-8-methyl-N-vanillyl-6-nonenarnide), a major pungent component of hot pepper, is known to exert antioxidative properties. In this study, we investigated the protective effects of capsaicin against chemical carcinogen-induced oxidative damage in rats. Male Sprague Dawley rats weighting 230~250 g were treated with chemical carcinogens such as 2-nitropropane (2NP) or n-methyl-N'-nitro-N-nitrosoguanidine (MNNG) after (or before) the administration of capsaicin at doses of 0.5, 1,5 mg/kg. The level of lipid peroxidation in rat liver was estimated by measuring the amounts of thiobarbituric acid reactive substances. The degree of oxidative DNA damage was evacuated by measuring a DNA adduct, 8-hydroxydeoxyguanosine (8-OHdG), in urine. Antioxidative activities of capsaicin and its metabolites in vitro were determined by the measurement of DPPH (1,1-diphenyl-2-picrylhydrazyl), a radical quencher. Significant inhibition of 2-NP induced lipid peroxidation was observed in the liver of the rat when treated with capsaicin. MNNG-induced urinary excretion of 8-OHdG was decreased by capsaicin treatment. Capsaicin and its metabolites inhibited net only the formation of free radicals, but also lipid peroxidation in vitro. Our results show that capsaicin may function as a free radical scavenger against chemical carcinogen-induced oxidative cellular damage in vivo. The observed antioxidative activities of capsaicin may play an important role in the process of chemoprevention.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.247-247
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• 1996

Previous work in our laboratory has shown that noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonists, MK-801, ketamine, dextrorphan and dextromethorphan cause a pronounced inhibition of apomorphine-induced cage climbing behavior in intact mice, suggesting the involvement of NMDA receptors in the glutamatergic modulation of dopaminergic function at the postsynaptic dopamine (DA) receptors: Therefore, in order to definitively establish the involvement of NMDA receptor in the apomorphine-induced dopaminergic response at the postsynaptic DA receptor, it is necessary to investigate whether or not the noncompetitive NMDA receptor antagonists would inhibit these phenomena not only in intact mice but also in the mice that are devoid of any involvement of indirect dopaminergic function. To minimize the risk of any indirect involvement of NMDA antagonists with DA neurons, vesicular DA stores were first depleted with reserpine.

• Natural Product Sciences
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• 제4권4호
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• pp.230-233
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• 1998

The methanol extract of Asparagus racemosus root was evaluated for its anti-inflammatory activity on carrageenin and serotonin-induced rat hind paw oedema models. The extract (200 and 400 mg/kg) showed maximum inhibition of oedema of 18.6% and 33.7% at 3 h with carrageenin and 22.2% and 40.5% at 5 h with serotonin-induced rat paw oedema respectively. The experimental models tested, where the effect produced by the extract was compared to that of phenylbutazone, a prototype non-steroidal anti-inflammatory drug.

• 생약학회지
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• 제24권3호
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• pp.197-202
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• 1993

Three components, fraxetin-8-glucoside, esculetin-6-glucoside and mannitol, were isolated from the stem bark of Fraxinus chiisanensis var. stenophylla, F. japonica var. intermedia and F. densata. The MeOH extract of the cortex of F. densata had the antiinflammatory activity on the carrageenin-induced paw edema in rat. The MeOH extracts of the cortex of all three Fraxinus spp. have the potent analgesic activity on the HOAc-induced writhing syndrome in mouse and the hepatoprotective activity on the $CCl_4-induced$ fatty liver in rat: protection of ballooning formation and inhibition of sGPT and sGOT increased by $CCl_4$.

• 대한수의학회지
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• 제39권1호
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• pp.70-76
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• 1999

Magnesium ($Mg^{2+}$) plays an important role in the regulation of a range of intracellular processes. Regulation of extracellular $Mg^{2+}$ contents was studied in the anesthetized Sprague-Dawley (SD) rats. Animals were injected intraperitoneally with sodium nitrite ($NaNO_2$), and circulating $Mg^{2+}$($[Mg^{2+}]c$) was measured after the injection and then 10 and 20 minutes later. A dose-dependent increase in $[Mg^{2+}]c$ was observed in animals injected with $NaNO_2$ at a dose of 10mg/kg or higher. Pretreatment with methylene blue prevented the $NaNO_2$-induced increase in $[Mg^{2+}]c$. $[Mg^{2+}]c$ displayed an inverse linear correlation with hemoglobin and exponential correlation during $NaNO_2$ injection. Injection of KCN or rotenone also induced an increase in $[Mg^{2+}]c$. An increase in $[Mg^{2+}]c$ was observed when respiration rate was reduced from 100/min (140ml/min) to 10/min (14ml/min) during 30 min. These results indicate that changes in $[Mg^{2+}]c$ inversely reflect alteration of ATP in a model of metabolic inhibition.

• BMB Reports
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• 제46권3호
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• pp.151-156
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• 2013

Phylogenetic and amino acid sequence analysis indicated that rice allene oxide synthase-1 (OsAOS1) is CYP74, and is clearly distinct from CYP74B, C and D subfamilies. Regio- and stereo-chemical analysis revealed the dual substrate specificity of OsAOS1 for (cis,trans)-configurational isomers of 13(S)- and 9(S)-hydroperoxyoctadecadienoic acid. GC-MS analysis showed that OsAOS1 converts 13(S)- and 9(S)-hydroperoxyoctadecadi(tri)enoic acid into their corresponding allene oxide. UV-Visible spectral analysis of native OsAOS1 revealed a Soret maximum at 393 nm, which shifted to 424 nm with several clean isobestic points upon binding of OsAOS1 to imidazole. The spectral shift induced by imidazole correlated with inhibition of OsAOS1 activity, implying that imidazole may coordinate to ferric heme iron, triggering a heme-iron transition from high spin state to low spin state. The implications and significance of a putative type II ligand-induced spin state transition in OsAOS1 are discussed.

• 생약학회지
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• 제45권3호
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• pp.214-219
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• 2014

Artemisia apiacea is a traditional herbal medicine using treatment of eczema and jaundice in Eastern Asia including China, Korea, and Japan. In this study, the three phytosterol constituents were isolated and identified from the hexane fraction of 80% aqueous methanol extract of A. apiacea. Compounds were isolated using open column chromatography (silica gel). Their chemical structures were also established using $^1H$-NMR and $^{13}C$-NMR. Moreover, neuroprotective activity of each compound against glutamate-induced neurotoxicity in hippocampal HT-22 cell line was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Furthermore, Inhibition of reactive oxygen species (ROS) and calcium ion ($Ca^{2+}$) accumulation were measured for elucidation of neuroprotective mechanism of isolated compounds. They showed that stigmasterol had neuroprotective activity against the glutamate-induced toxicity by inhibition of ROS and $Ca^{2+}$ production. In conclusion, isolated compound of A. apiacea might be useful for therapeutic agent against neurodegenerative diseases.

• Archives of Pharmacal Research
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• 제29권5호
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• pp.375-383
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• 2006

The anti platelet effects of a novel guanidine derivative, KR-32570 ([5-(2-methoxy-5-chlorophenyl) furan-2-ylcarbonyl]guanidine), were investigated with an emphasis on the mechanisms underlying its inhibition of collagen-induced platelet aggregation. KR-32570 significantly inhibited the aggregation of washed rabbit platelets induced by collagen $(10{\mu}g/mL)$, thrombin (0.05 U/mL), arachidonic acid $(100{\mu}M)$, a thromboxane (TX) $A_2$ mimetic agent U46619 (9,11-dideoxy-9,11-methanoepoxy-prostaglandin $F_2,\;1{\mu}M$) and a $Ca^{2+}$ ATPase inhibitor thapsigargin $(0.5{\mu}M)$ ($IC_{50}$ values: $13.8{\pm}1.8,\;26.3{\pm}1.2,\;8.5{\pm}0.9,\;4.3{\pm}1.7\;and\;49.8{\pm}1.4{\mu}M$, respectively). KR-32570 inhibited the collagen-induced liberation of $[^3H]$arachidonic acid from the platelets in a concentration dependent manner with complete inhibition being observed at $50{\mu}M$. The $TXA_2$ synthase assay showed that KR-32570 also inhibited the conversion of the substrate $PGH_2$ to $TXB_2$ at all concentrations. Furthermore, KR-32570 significantly inhibited the $[Ca^{2+}]_i$ mobilization induced by collagen at $50{\mu}M$, which is the concentration that completely inhibits platelet aggregation. KR-32570 also decreased the level of collagen $(10{\mu}g/mL)$induced secretion of serotonin from the dense-granule contents of platelets, and inhibited the NHE-1-mediated rabbit platelet swelling induced by intracellular acidification. These results suggest that the antiplatelet activity of KR-32570 against collagen-induced platelet aggregation is mediated mainly by inhibiting the release of arachidonic acid, $TXA_2$ synthase, the mobilization of cytosolic $Ca^{2+}$ and NHE-1.

• BMB Reports
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• 제28권4호
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• pp.316-322
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• 1995

The GTPase activating protein (GAP) can function both as a negative regulator and an effector of $p21^{ras}$. Overexpression of GAP in NIH-3T3 cells has been shown to inhibit transformation by ms or src. To investigate the function of GAP in a differentiative system, we overexpressed this protein in the nerve growth factor (NGF)-responsive PC12 cell line. Two-fold overexpression of GAP caused a delay of several days in the onset of NGF- but not FGF-induced neuronal differentiation of PC12 cells. However, the NGF-induced activation or tyrosine phosphorylation of upstream (Trk, PLC-${\gamma}1$, SHC) and downstream (B-Raf and $p44^{mapk/erk1}$) components of $p21^{ras}$, signalling cascade was not altered by GAP overexpression. Therefore, the change of phenotype induced by GAP was probably not due to GAP functioning as a negative regulator of $p21^{ras}$. Rather, we found that NGF-induced tyrosine phosphorylation of SNT, a specific target of neurotrophin-induced tyrosine kinase activity, was inhibited by GAP overexpression. SNT is thought to function upstream or independent of $p21^{ras}$. Thus in PC12 cells, overexpressed GAP may control the rate of neuronal differentiation through a pathway involving SNT rather than the $p21^{ras}$ signalling pathway.

• 한국식품영양학회지
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• 제9권3호
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• pp.294-298
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• 1996

By the 505 chromotest which utilized Escherichia bolt PQ 37, Korean medicinal plants had been screened to Investigate the antimutagenic effect to aflatoxin B1(AFBl). Ikmocho(IMC, Leonurus sibiricus L.) was extracted with hot water. The extract was not found to be mutagenic in the Salmonella mutation test with or without metabolic activation, and the extract was showed to possess the antimutagenic properties towards AFB1-induced metation. The mutagenicity of AFB1 was inhibited by methanol soluble fracstion (IMC-MS) in dose-dependent. However, water-soluble fraction exhibited comutagenic activity. The greatest inhibitory effect of IMC-MS on AFB1 mutagenicity occurred when IMC-MS was first incubated, AFB1 followed by a second incubation with the cells and 59 mixture. Also lower inhibition was occurred when S9 mixtures were first incubated, with IMC-MS followed by a second incubation with AFBI. The results of the sequential incubation study support the probability that one mechanism of inhibition could involve the formation of chemical complex between IMC-MS and AFB1 rather than deactivation of S9 enzyme.