• Journal of Plant Biology
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• 제33권4호
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• pp.309-314
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• 1990

Effect of mannose on auxin-induced ethylene production in corn (Zea mays L.) coleoptiles was studied. Auxin induced ethylene production decreased in proportion to mannose concentrations. The inhibitory effect of mannose appeared after 2 h of incubation. Ethylene production was significantly depressed by mannose at high concentration (10-5M-10-4M) of indole acetic acid (IAA), but not at low concentrations (10-8M-10-6M). The inhibition of auxin-induced ethylene production by mannose was specific, since other sugars such as galactose, glucose, sucrose and mannitol did not have an inhibitory effect. In an effort to elucidate mechanisms of mannose the effect on the auxin induced ethylene production, effect of the sugar on ACC synthase activity and ACC induced ethylene production was studied. Mannose failed to inhibit ACC mediated ethylene production, but decreased both the ACC content and ACC synthase activity in the tissue. These results suggest that the inhibitory effect of mannose on auxin induced ethylene production results from suppression of auxin induction of ACC synthase.

• Journal of Plant Biology
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• 제32권4호
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• pp.265-274
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• 1989

The effect of Ca2+ on auxin-induced ehtylene production in etiolated mungbean (Vigna radiata W.) hypocotyls was studied. Auxin-induced ethylene production by mungbean seedlings which had been germinated in the presence of 5-10mM Ca2+ (High Ca2+ ; HC) is greater than that by seedlings which had been germinated in distilled water (Low Ca2+ ; LC). The effect of Ca2+ on auxin-induced ethylene production was greatly increased after 12hr of incubation period. The stimulation of auxin-induced ethylene production by Ca2+ was specific, since divalent cations, such as Mg2+ and Mn2+ did not enhance auxin-induced ethylene production. Calcium also promoted ethylene evoluation induced by methionine and 1-Aminocyclopropane-1-carboxylic acid(ACC). The effect of Ca2+ on auxin-induced ethylene production was not caused by increase in free IAA or ACC contents of hypocotyl tissue. Dimethyl sulfoxide and Triton X-100, that disrupts the emembranes, inhibited ethylene production to a greater extent in LC segments than in HC segments. Addition of Ca2+ to the incubation medium for LC segments resulted in enchancement of ethylene production probalby because the membrane integrity is supported under these conditions. Comparison of activity of Ethylene Forming Enzyme(EFE) in LC and HC hypocotyl segments indicated that the enzyme activity of HC was about 2 times higher than that of L.C. It is suggested that Ca2+ increases the activity of plasma membrane-bound EFE through its stabilizing effect onn the membrane, which in turn brings about promotion of ethylene production.

• 한국식품위생안전성학회지
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• 제11권4호
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• pp.227-234
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• 1996

This study was designed to characterize endotoxin-induced prostaglandin production in primary cultured rat vascular smooth muscle cells (VSMC). The time course for prostaglandin synthesis in lipopolysaccharide (LPS)-stimulated VSMC showed that the maximum production was reached in 12 hours. LPS induced prostaglandin H2 synthase (PGHS) activity in VSMC and the time course profile in the changes of PGHS activity paralleled that of total prostaglandin production. Differential treatment showed that 4 hours' exposure to LPS was enough for the maximum effect on the prostaglandin production and this effect was completely inhibited by the co-treatment of actinomycin D, a transcription inhibitor. These results suggest that LPS effect might be determined within 4 hours. Actinomycin D increased PGHS activity without affecting prostaglandin production if added 4 hours after LPS treatment. On the other hand, cyclogeximide, a translation inhibitor, augmented LPS-induced prostaglandin production if treated during first four hours, but it inhibited LPS-induced PGHS activity regardless of treatment schedule. These results suggest the existence of multiple regulating mechanisms in the LPS-induced prostaglandin synthesis.

• Journal of Plant Biology
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• 제32권4호
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• pp.343-350
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• 1989

Calcium promoted ethylene production from mungbean hypocotyl segments incubated in the presence of either auxin or cytokinin (kinetin). Time course studies indicated that the calcium effect on ethylene production had a longer latent period (about 6 h) in combination with kinetin than with auxin. Studies on the effects of agents that are known to interfere with either action or transport (uptake) of calcium on ethylene biosynthesis indicated different patterns between auxin- and kinetin-treated tissues. Auxin-induced ethylene production was inhibited by the calmodulin inhibitor, trifluoperazine (TFP), and this inhibition was overcome by high concentrations of calcium applied, but TFP had no significant effect on kinetin-induced ethylene production regardless of calcium in the medium. The calcium channel blocker, verapamil, inhibited auxin-induced, but had little effect on kinetin-induced, ethylene producton. In vivo activity of "ethylene forming enzyme (EFE)" was found to be substantially promoted by calcium treatment. The enzyme activity was further increased by kinetin when segments were simultaneously treated with calcium, but auxin did not have such an effect.an effect.

• 약학회지
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• 제60권1호
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• pp.21-28
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• 2016

Systemic lupus erythematosus (SLE) is characterized by dysregulatory production of proinflammatory cytokines and helper T (Th) cytokine-dependent autoantibody production. This study aims to investigate the protective effect of baicalin on the dysregulatory production of proinflammatory cytokines and Th cytokines in pristane-induced lupus mice. Mice were received i.p. a single injection of 0.5 ml of pristane, and then, later about 3 months, were used as a pristane-induced lupus model. The pristane-induced lupus mice were administrated orally with baicalin 50 mg/kg once in a day for 10 days. Immune cells obtained from the pristane-primed lupus control group (lupus control) and baicalin-treated pristaneprimed lupus mouse group (BAC lupus) were cultured for 24 h or 36 h with/without mitogens. These results demonstrated that LPS-induced production of macrophage and splenic TNF-${\alpha}$ and Con A-induced production of thymic IFN-${\gamma}$ were attenuated in BAC lupus compared to lupus control, while LPS-stimulated production of macrophage IL-10, Con A-stimulated production of splenic IL-10 and, $PGE_2$-reduced production of splenic IFN-${\gamma}$ enhanced. Therefore, these findings suggest that baicalin may protect from autoimmunity and disease activity in lupus via modulatory effect of proinflammatory cytokine overproduction and Th cytokine imbalance.

• 동의생리병리학회지
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• 제28권4호
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• pp.384-389
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• 2014

The purpose of this study is to investigate the modulatory effect of oroxylin A on hydrogen peroxide production in TM4 mouse testis sertoli cells induced by the synthetic analog of double-stranded RNA [polyinosinic-polycytidylic acid]. Hydrogen peroxide production was measured by dihydrorhodamine 123 (DHR) assay. Oroxylin A significantly inhibited the polyinosinic-polycytidylic acid (PIC)-induced production of hydrogen peroxide for 0.5, 2, 12, 18, and 24 hr incubation at the concentrations of 5, 10, 25, and $50{\mu}M$ in TM4 (P < 0.05) in dose dependent manner. These results suggest that oroxylin A has a protective effect against PIC-induced cellular toxicity with its inhibition of hydrogen peroxide production in PIC-induced sertoli cells.

• Journal of Plant Biology
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• 제35권4호
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• pp.409-414
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• 1992

Quercetin(3,5,7,3'-4'-OH-flavone)이 보리(Hordeum vulgare var. hexastichon ASCHERS.) 자엽초 조직에서 옥신유발 에틸렌 생성을 현저히 촉진시켰다. $3{\times}10^{-5}\;M$의 quercetin에서 배양한 보리 자엽초 조직에서 옥신 유발 에틸렌 생성은 4시간 이후부터 증가되기 시작하여 8시간 이후에는 200%까지 증가되었다. Quercetin은 내재옥신인 indol-3-acetic acid(IAA)에 의한 에틸렌 생성은 촉진하나 합성 옥신인 2,4-dichlorophenoxyacetic acid(2,4-D)나 naphthaleneacetic acid(NAA)에 의한 에틸렌 생성에는 아무런 영향을 주지 않았다. 또한, 에틸렌 전구체인 1-aminocyclopropen-1-carboxylic acid(ACC) 유발 에틸렌 생성에도 촉진효과가 없었다. 이러한 결과는 에틸렌 생성에 대한 quercetin의 효과는 ACC 전단계에 작용한다는 것을 의미한다. Quercetin이 IAA 대사에 어떠한 영향을 미치는지 확인한 결과 조직을 quercetin에 1시간 배양시켰을 때 조직내 IAA oxidase 효소 활성이 90% 감소되었으며, IAA conjugation에는 별 영향을 미치지 않았다. 따라서, 옥신 유발 에틸렌 생성에 대한 quercetin의 촉진작용은 quercetin이 IAA oxidase의 활성을 억제시켜 높아진 IAA 수준이 옥신 유발 에틸렌 생성을 증가시키는 것으로 생각된다.

• 동의생리병리학회지
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• 제25권6호
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• pp.1039-1043
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• 2011

The purpose of this study is to investigate the modulatory effect of emodin on hydrogen peroxide production in human blastoma SH-SY5Y cells induced by the synthetic analog of double-stranded RNA [polyinosinic-polycytidylic acid]. Hydrogen peroxide production was measured by dihydrorhodamine 123 (DHR) assay. Emodin significantly inhibited the polyinosinic-polycytidylic acid (PIC)-induced production of hydrogen peroxide for 0.5, 2, 12, 18, and 24 hr incubation at the concentrations of 5, 10, 25, and 50 uM in SH-SY5Y (P < 0.05) in dose dependent manner. These results suggest that emodin has neuroprotective property related with its inhibition of hydrogen peroxide production in PIC-induced neuronal cells.

• 한국기후변화학회지
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• 제7권1호
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• pp.59-68
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• 2016

The world's major countries have focused on the renewable energy industry as the solution to climate change and the energy crisis. Nevertheless, there are no studies on the economic effects of the renewable energy industry. This study analyzed the economic effects of Korea's renewable energy industry by using the 2010 Input-Output Table. It is estimated that Korea's renewable energy industry made a production-induced effect of 2.0262 won, and a value-added-induced effect of 0.6138 won through an increase in output growth of 1 won, and an employment-induced effect of 2.3046 labors through an increase in output growth of 1 billion won. Both the effect ratio and the response ratio were greater than 1, which means the renewable energy industry is an intermediate manufacturing industry whose forward linkage effect and backward linkage effects are large. These results show differences with previous studies that classified electricity sector and renewable energy industry into final primary production industries. It is expected that the economic effects of the renewable energy industry will become greater in the future. Therefore, research on statistics related to the renewable energy industry is needed for more precise analysis.

• The Korean Journal of Physiology and Pharmacology
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• 제3권4호
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• pp.447-454
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• 1999

The production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS) are known to be modulated by a variety of factors. Recent study showed that endotoxin-induced NO synthesis and iNOS expression were greatly enhanced by elevation of extracellular glucose concentration in murine macrophages. Although this was suggested to be due to the activation of protein kinase C (PKC) via sorbitol pathway, there was lack of evidence for this speculation. This study was performed to delineate the underlying intracellular mechanisms of glucose-enhancing effect on endotoxin-induced NO production in Raw264.7 macrophages. The levels of NO release induced by lipopolysaccharide (LPS) significantly increased by the treatment of glucose in a concentration dependent manner and also, this effect was observed in LPS-preprimed cells. Concurrent incubation of cells with PKC inhibitors, H-7 or chelerythrine, and LPS resulted in the diminution of NO production regardless of glucose concentration but this was not in the case of LPS-prepriming, that is, chelerythrine showed a minimal effect on the glucose- enhancing effect. PMA, a PKC activator, did not show any significant effect on glucose-associated NO production. Modulation of sorbitol pathway with zopolrestat, an aldose reductase inhibitor, did not affect LPS-induced NO production and iNOS expression under high glucose condition. And also, sodium pyruvate, which is expected to normalize cytosolic $NADH/NAD^+$ ratio, did not show any significant effect at concentrations of up to 10 mM. Glucosamine marginally increased the endotoxin-induced nitrite release in both control and high glucose treated group. 6-diazo-5-oxonorleucine (L-DON) and azaserine, glutamine: fructose- 6-phosphate amidotransferase (GFAT) inhibitors, significantly diminished the augmentation effect of high glucose on endotoxin-induced NO production. On the other hand, negative modulation of GFAT inhibitors was not reversed by the treatment of glucosamine, suggesting the minimal involvement, if any, of glucosamine pathway in glucose-enhancing effect. In summary, these results strongly suggest that the hexosamine biosynthesis pathway and the activation of PKC via sorbitol pathway do not contribute to the augmenting effect of high glucose on endotoxin induced NO production in macrophage-like Raw264.7 cells.