• Title/Summary/Keyword: Reduced Reaction Mechanism

Search Result 205, Processing Time 0.029 seconds

The Study of Free Radical Scavenging Effect of Lycii Fructus by Liver Injury of Rats (백서 간손상에 의한 구기자의 유리자유기 소거능에 관한 연구)

  • Yoon Sang Ju;Jung Sun Yeong;Kim Young Mi;Ha Ki Tae;Kim Cheorl Ho;Kim Dong Wook;Kim June Ki;Choi Dall Yeong
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.17 no.1
    • /
    • pp.91-100
    • /
    • 2003
  • In the present study, we investigated the protective effect of the Lycii Fructus water extracts (LFE) against CCl4-induced hepatotoxicity and the mechanism underlying these protective effects in the rats. The pretreatment of LFE has shown to possess a significant protective effect by lowering the serum alanine and aspartate aminoteansferase (AST and ALT) and alkaline phosphatase (ALP). This hepatoprotective action was confirmed by histological observation, In addition, the pretreatment of LFE prevented the elevation of hepatic malondialdehyde (MDA) formation and the depletion of reduced glutathione (GSH) content and catalase activity in the liver of CC1₄-injected rats. The LFE also displayed hydroxide radical scavenging activity in a dose-dependent manner (IC50 = 83.6 μg/ml), as assayed by electron spin resonance (ESR) spin-trapping technique. Moreover, the expression of cytochrome P450 2E1 (CYP2E1) mRNA, as measured by reverse transcriptase-polymerase chain reaction (RT-PCR), was significantly decreased in the liver of LFE-pretreated rats when compared with that in the liver of control group. Based on these results, it was suggested that the hepatoprotective effects of the LFE may be related to antioxidant effects and regulation of CYP2E1 gene expression.

Effect of Zhongyi paste on inflammatory pain in mice by regulation of the extracellular regulated protein kinases 1/2-cyclooxygenase-2-prostaglandin E2 pathway

  • Xiao, Ailan;Wu, Chuncao;Kuang, Lei;Lu, Weizhong;Zhao, Xin;Kuang, Zhiping;Hao, Na
    • The Korean Journal of Pain
    • /
    • v.33 no.4
    • /
    • pp.335-343
    • /
    • 2020
  • Background: Zhongyi paste is a traditional Chinese medicine herbal paste that is externally applied to reduce inflammation and relieve pain. Methods: An acute foot swelling inflammation model in C57BL/6J mice was established by carrageenan-induced pathogenesis. Zhongyi paste raised the pain threshold and also reduced the degree of swelling in mice with carrageenan-induced foot swelling. Results: Analysis indicated that serum tumor necrosis factor-alpha, interleukin-1 beta, and prostaglandin E2 (PGE2) cytokine levels and PGE2 levels in the paw tissue of the mice were decreased by Zhongyi paste treatment. The quantitative polymerase chain reaction and western blot results showed that Zhongyi paste downregulated the mRNA and protein expression of extracellular signal-regulated kinase 1/2 (ERK1/2), and cyclooxygenase-2 (COX-2), and also downregulated the mRNA expression of PGE2. At the same time, the Zhongyi paste exerted a stronger effect as an external drug than that of indomethacin, which is an oral drug, and voltaren, which is an externally applied drug. Conclusions: Our results indicated that Zhongyi paste is a very effective drug to reduce inflammatory swelling of the foot, and its mechanism of action is related to regulation of the ERK1/2-COX-2-PGE2 pathway.

Molecular Cloning and Characterization of an NADPH Quinone Oxidoreductase from Kluyveromyces marxianus

  • Kim, Wook-Hyun;Chung, Ji-Hyung;Back, Jung-Ho;Choi, Ju-Hyun;Cha, Joo-Hwan;Koh, Hun-Yeoung;Han, Ye-Sun
    • BMB Reports
    • /
    • v.36 no.5
    • /
    • pp.442-449
    • /
    • 2003
  • NAD(P)H quinone oxidoreductase is a ubiquitous enzyme that is known to directly reduce quinone substrates to hydroquinones by a two-electron reaction. We report the identification of NADPH quinone oxidoreductase from Kluyveromyces marxianus (KmQOR), which reduces quinone substrates directly to hydroquinones. The KmQOR gene was sequenced, expressed in Escherichia coli, purified, and characterized. The open-reading frame of the KmQOR gene consists of 1143 nucleotides, encoding a 380 amino acid polypeptide. The nucleotide sequence of the KmQOR gene was assigned to EMBL under accession number AY040868. The $M_r$ that was determined by SDS-PAGE for the protein subunit was about 42 kDa, and the molecular mass of the native KmQOR was 84 kDa, as determined by column calibration, indicating that the native protein is a homodimer. The KmQOR protein efficiently reduced 1,4-benzoquinone, whereas no activities were found for menadiones and methoxyquinones. These observations, and the result of an extended sequence analysis of known NADPH quinone oxidoreductase, suggest that KmQOR possesses a different action mechanism.

Inhibition of the Expression of Matrix Metalloproteinases in Articular Chondrocytes by Resveratrol through Affecting Nuclear Factor-Kappa B Signaling Pathway

  • Kang, Dong-Geun;Lee, Hyun Jae;Lee, Choong Jae;Park, Jin Sung
    • Biomolecules & Therapeutics
    • /
    • v.26 no.6
    • /
    • pp.560-567
    • /
    • 2018
  • In the present study, we tried to examine whether resveratrol regulates the expression of matrix metalloproteinases (MMPs) through affecting nuclear factor-kappa B ($NF-{\kappa}B$) in articular chondrocytes. Rabbit articular chondrocytes were cultured in a monolayer, and reverse transcription-polymerase chain reaction (RT-PCR) was used to measure interleukin-${\beta}$ ($IL-1{\beta}$)-induced gene expression of MMP-3, MMP-1, MMP-13, a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4), ADAMTS-5 and type II collagen. Effect of resveratrol on $IL-1{\beta}$-induced secretion of MMP-3 was investigated in rabbit articular chondrocytes using western blot analysis. To elucidate the action mechanism of resveratrol, effect of resveratrol on $IL-1{\beta}$-induced $NF-{\kappa}B$ signaling pathway was investigated in SW1353, a human chondrosarcoma cell line, by western blot analysis. The results were as follows: (1) resveratrol inhibited the gene expression of MMP-3, MMP-1, MMP-13, ADAMTS-4, and ADAMTS-5, but increased the gene expression of type II collagen; (2) resveratrol reduced the secretion of MMP-3; (3) resveratrol inhibited $IL-1{\beta}$induced activation (phosphorylation) of inhibitory kappa B kinase (IKK), and thus phosphorylation and degradation of inhibitory kappa $B{\alpha}$ ($I{\kappa}B{\alpha}$); (4) resveratrol inhibited $IL-1{\beta}$-induced phosphorylation and nuclear translocation of $NF-{\kappa}B$ p65. This, in turn, led to the down-regulation of gene expression of MMPs in SW1353 cells. These results suggest that resveratrol can regulate the expression of MMPs through affecting $NF-{\kappa}B$ by directly acting on articular chondrocytes.

The Effects of Woohwangcheongsim-won on Reperfusion Following Middle Cerebral Artery Occlusion in Rats (우황청심원이 중대뇌동맥 결찰로 유발된 뇌허혈에 미치는 영향)

  • 조규선;정승현;신길조;이원철
    • The Journal of Korean Medicine
    • /
    • v.22 no.1
    • /
    • pp.78-89
    • /
    • 2001
  • Objectives : The purpose of this investigation is to evaluate the effects of Woohwangcheongsim-won on reperfusion following MCA occlusion in rats. Methods : To evaluate the effect of Woohwangcheongsim-won on reperfusion following MCA occlusion, the volume of cerebral ischemia and edema were measured and the change of the CAI pyramidal neuron in the hippocampus was investigated by light microscopy. And the changes of several neurotransmitters and enzymes were investigated with the immunohistochemical methods. Results : 1. The volume of the control group, which was ischemic-damaged was 23.6%, and that of the sample group was 13.5%. 2. The voluminalratio of the right/left hemisphere was 116 in the control group, and that of the sample group was 107. 3. The pyramidal cells of CAI area in the control group were greatly damaged. The cells were changed into discontinuous and unsystematic forms, and nuclei, and cytoplasms were shrunk. On the other hand, the cells of the sample group were less damaged. 4. On the immunohistochemical methods, the sensitivities of GABA, NOS, DBH in the control group were increased, and those of synapsin and $eEF-l{\alpha}$ were decreased as compared with the normal group. NOS and DBH which were negative in the normal group showed positive reaction. On the other hand, the sensitivities of GABA, NOS and DBH in the sample group were decreased, but those of NPY, synapsin, CaMKII and $eEF-l{\alpha}$ were increased as compared with the control group. Conclusions : Woohwangcheongsim-won reduced the volume of cerebral ischemia and edema, and minimized the damage of pyramidal cells. The mechanism was related to protein synthesis, such as synapsin, ${\alpha}CaMKII$ and $eEF-l{\alpha}$, which resist neurotoxicity of glutamate receptors.

  • PDF

Lin28a attenuates TGF-β-induced renal fibrosis

  • Jung, Gwon-Soo;Hwang, Yeo Jin;Choi, Jun-Hyuk;Lee, Kyeong-Min
    • BMB Reports
    • /
    • v.53 no.11
    • /
    • pp.594-599
    • /
    • 2020
  • Lin28a has diverse functions including regulation of cancer, reprogramming and regeneration, but whether it promotes injury or is a protective reaction to renal injury is unknown. We studied how Lin28a acts in unilateral ureteral obstruction (UUO)-induced renal fibrosis following unilateral ureteral obstruction, in a mouse model. We further defined the role of Lin28a in transforming growth factor (TGF)-signaling pathways in renal fibrosis through in vitro study using human tubular epithelium-like HK-2 cells. In the mouse unilateral ureteral obstruction model, obstruction markedly decreased the expression of Lin28a, increased the expression of renal fibrotic markers such as type I collagen, α-SMA, vimentin and fibronectin. In TGF-β-stimulated HK-2 cells, the expression of Lin28a was reduced and the expression of renal fibrotic markers such as type I collagen, α-SMA, vimentin and fibronectin was increased. Adenovirus-mediated overexpression of Lin28a inhibited the expression of TGF-β-stimulated type I collagen, α-SMA, vimentin and fibronectin. Lin28a inhibited TGF-β-stimulated SMAD3 activity, via inhibition of SMAD3 phosphorylation, but not the MAPK pathway ERK, JNK or p38. Lin28a attenuates renal fibrosis in obstructive nephropathy, making its mechanism a possible therapeutic target for chronic kidney disease.

Upregulation of Heme Oxygenase-1 as an Adaptive Mechanism against Acrolein in RAW 264.7 Macrophages

  • Lee, Nam-Ju;Lee, Seung-Eun;Park, Cheung-Seog;Ahn, Hyun-Jong;Ahn, Kyu-Jeung;Park, Yong-Seek
    • Molecular & Cellular Toxicology
    • /
    • v.5 no.3
    • /
    • pp.230-236
    • /
    • 2009
  • Acrolein, a known toxin in cigarette smoke, is the most abundant electrophilic $\alpha$, $\beta$-unsaturated aldehyde to which humans are exposed in a variety of environmental pollutants, and is also product of lipid peroxidation. Increased unsaturated aldehyde levels and reduced antioxidant status plays a major role in the pathogenesis of various diseases such as diabetes, Alzheimer's and atherosclerosis. The findings reported here show that low concentrations of acrolein induce heme oxygenase-1 (HO-1) expression in RAW 264.7 macrophages. HO-1 induction by acrolein and signal pathways was measured using reverse transcription-polymerase chain reaction, Western blot and immunofluorescence staining analyses. Inhibition of extracellular signal-regulated kinase activity significantly attenuated the induction of HO-1 protein by acrolein, while suppression of Jun N-terminal kinase and p38 activity did not affect induction of HO-1 expression. Moreover, rottlerin, an inhibitor of protein kinase $\delta$, suppressed the upregulation of HO-1 protein production, possibly involving the interaction of NF-E2-related factor 2 (Nrf2), which has a key role as a HO-1 transcription factor. Acrolein elevated the nuclear translocation of Nrf2 in nuclear extraction. The results suggest that RAW 264.7 may protect against acrolein-mediated cellular damage via the upregulation of HO-1, which is an adaptive response to oxidative stress.

AN EXPERIMENTAL STUDY ON THE CHEMOPREVENTIVE EFFECT OF CHLOROPHYLLIN IN HAMSTER CHEEK POUCH TUMOR INDUCED BY 7, 12-DIMETHYLBENZ[A]ANTHRACENE (7, 12-dimethylbenz[a]anthracene(DMBA)로 유발된 햄스터 협낭암에서 chlorophylln의 암예방효과에 관한 실험적 연구)

  • Yoon, Kyu-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • v.26 no.2
    • /
    • pp.137-145
    • /
    • 2000
  • Carcinogenesis is a multi-stage process that generally consists of at least three steps; initiation, promotion, and progression. If one of these carcinogenic steps were suppressed or delayed, the cancer could be prevented. Cancer chemoprevention is defined to be inhibition or reversal of the carcinogenic process by the specific chemical agents and is a novel approach to cancer management alternative to conventional chemotherapy. Chlorophylln(CHL), a water-soluble derivative of chlorophyll, containing sodium and copper, has been known to be strong antimutagen in several test systems, but its mechanism of antimutagenic action is unknown. In the present experiment, the possibility of CHL as chemopreventive drugs on 7,12-dimethylbenz[a]anthracene(DMBA)-induced hamster buccal pouch carcinogenesis was investigated by mutagenicity test, carcinogenicity test, and frequency or spectrum of H-ras mutations in the both of DMBA-induced and chlorophylln-pretreated-DMBA induced tumor by polymerase chain reaction and non-isotopic restriction fragment length polymorphism. The treatment of CHL reduced the yields and multiplicity of the 0.5% DMBA-induced tumor, 86% to 62.5% and $3.7{\pm}0.6$ to $1.4{\pm}0.3$, respectively. The occurrence of histidine revertant by $20{\mu}mole$ DMBA was inhibited 25.6 to 81.7% by 1 to $5{\mu}M$ CHL in a dose-dependent manner. The mutation rates of H-ras gene in DMBA-induced and CHL-pretreated-DMBA induced tumor were 96%, 94% of which the most mutations were in codon 12/13. These results suggest that CHL inhibits the carcinogenic action of DMBA by the formation of complex between CHL and DMBA or the inhibition of the activation of DMBA in vivo. But CHL did not affect the mutation rates or its spectrum in already formed tumor.

  • PDF

High-Voltage Liquid-Electrolyte Microbatteries Inspired from Electric Eels (전기뱀장어의 전기발생을 모사한 고전압 액체 전해질 미소전지)

  • Kim, Mun-Chul;Cho, Young-Ho
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.33 no.5
    • /
    • pp.469-473
    • /
    • 2009
  • We present high-voltage liquid-electrolyte microbatteries, inspired from the high-voltage generation mechanism of electric eels using serially connected multiple-cell arrays. In the microbatteries, we purge air into the electrolyte filled in a channel layer to isolate serially connected multiple cell arrays using three surface-tension valves (cell-front, outlet, and cell-end valves). Compared to the previous multi-cell stack or interconnection, present microbatteries provide a reduced multi-cell charging time. We have designed and characterized four different prototypes C1, C10, C20, and C40 having 1, 10, 20, and 40 cells, respectively. In the experimental study, the threshold pressures of cell-front, outlet, and cell-end valves were measured as $460{\pm}47$, $1,000{\pm}53$, and $2,800{\pm}170$ Pa, respectively. The average charging time for C40 was measured as $26.8{\pm}4.9$ seconds where the electrolyte and air flow-rates are 100 and $10{\mu}l/min$, respectively. Microbatteries showed the maximum voltage of 12 V (C40), the maximum power density of $110{\mu}W/cm^2$ (C40), and the maximum power capacity of $2.1{\mu}Ah/cm^2$ (C40). We also proposed a tapered-channel to remove the reaction gas from the cell chamber using a surface tension effect. The present microbatteries are applicable to high-voltage portable power devices.

The Study of Protective Effect of Puerariae Radix against $CC1_4$-induced Hepatotoxicity ($CC1_4$로 유발된 백서의 간손상에 대한 갈근의 간보호작용 연구)

  • Hyun Dong Hwan;Jung Sun Yeong;Jung Sang Shin;Ha Ki Tae;Kim Cheorl Ho;Kim Dong Wook;Kim June Ki;Choi Dall Yeong
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.17 no.2
    • /
    • pp.297-307
    • /
    • 2003
  • In the present study, we investigated the protective effect of the Puerarie Radix water extract (PRE) against CCl₄-induced hepatotoxicity and the mechanism underlying these protective effects in the rats. The pretreatment of PRE has shown to possess a significant protective effect by lowering the serum alanine and aspartate aminoteansferase (AST and ALT) and alkaline phosphatase (ALP). This hepatoprotective action was confirmed by histological observation. In addition, the pretreatment of PRE prevented the elevation of hepatic malondialdehyde (MDA) formation and the depletion of reduced glutathione (GSH) content and catalase activity in the liver of CC1₄-injected rats. The PRE also displayed hydroxide radical scavenging activity in a dose-dependent manner (IC50 = 83.6 μg/ml), as assayed by electron spin resonance (ESR) spin-trapping technique. Moreover, the expression of cytochrome P450 2E1 (CYP2E1) mRNA, as measured by reverse transcriptase-polymerase chain reaction (RT-PCR), was significantly decreased in the liver of PRE-pretreated rats when compared with that in the liver of control group. Based on these results, it was suggested that the hepatoprotective effects of the PRE may be related to antioxidant effects and regulation of CYP2E1 gene expression.