• Title/Summary/Keyword: plant physiology

Search Result 441, Processing Time 0.029 seconds

Inhibition of $A{\beta}42$ Fibrillation and Toxicity with ${\beta}$-Asarone ($A{\beta}42$의 섬유화 및 독성에 대한 ${\beta}$-Asarone의 저해 효과)

  • Kim, Jia;Lee, Chul Won;Lee, Boo Kyun;Lee, Jang Cheon;An, Won Gun
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.28 no.3
    • /
    • pp.317-321
    • /
    • 2014
  • Amyloid-${\beta}$ protein ($A{\beta}$) is a pathological component of Alzheimer's disease (AD) by participating in the senile plaque formation in the patient's brain. Although the exact mechanism of $A{\beta}$ toxicity is not fully elucidated, it is considered to be closely related to its fibrillation process. For prevention of AD, recent studies have suggested various small molecules which inhibit $A{\beta}$ fibrillation. In this report, ${\beta}$-asarone found in acorus plant has been investigated as an anti-amyloid molecule. ${\beta}$-Asarone was demonstrated to prevent in vitro fibrillation of $A{\beta}$ by inducing the oligomer formation that obviously decreased cytotoxicity. Therefore, ${\beta}$-asarone could be suggested as an inhibitory agent of $A{\beta}$ fibrillation and toxicity, which would help us not only to understand underlying principle of amyloidogenesis mechanism but also to develop a controlling strategy toward AD.

The Optimization for Functional Expression of Arabidopsis Thaliana AtPIP2-1 in Xenopus laevis Oocyte (Xenopus oocyte에서 애기장대 AtPIP2-1 활성측정을 위한 발현 최적화 조건 규명)

  • Kim, Hyun-Mi;Hwang, Hyun-Sik;Lee, Suk-Chan;Jo, Su-Hyun;Kim, Beom-Gi
    • Journal of Applied Biological Chemistry
    • /
    • v.53 no.4
    • /
    • pp.189-194
    • /
    • 2010
  • We confirmed the hypo-osmotic shock strengths and duration, different type of vectors, and subcelluar localization to identify the optimum analysis condition of plant aquaporin activity in Xenopus ooctye using Arabidopsis thaliana AtPIP2-1 gene. Six minutes and 1/5ND buffer hypoosmotic shock treatment was the best condition to show the maximum swelling of Xenopus oocytes where AtPIP2-1 was expressed using pcDNA3.1 vector. AtPIP2-1 protein was expressed more efficiently in pGEMHE vector which has 5' and 3' UTR (untranslation region) of Xenopus ${\beta}$-GLOBIN gene in multiple cloning site than in pcDNA3.1 vector. Also green fluorescence of GFP fused to AtPIP2-1 was detected onto oocyte plasmamembrane where is the proper subcellular localization target of AtPIP2-1.

The Stress-Responsive and Host-Oriented Role of Nonribosomal Peptide Synthetases in an Entomopathogenic Fungus, Beauveria bassiana

  • Liu, Hang;Xie, Linan;Wang, Jing;Guo, Qiannan;Yang, Shengnan;Liang, Pei;Wang, Chengshu;Lin, Min;Xu, Yuquan;Zhang, Liwen
    • Journal of Microbiology and Biotechnology
    • /
    • v.27 no.3
    • /
    • pp.439-449
    • /
    • 2017
  • Beauveria bassiana infects a number of pest species and is known to produce insecticidal substances, such as the nonribosomal peptides (NRPs) beauvericin and bassianolide. However, most NRPs and their biological roles in B. bassiana remain undiscovered. To identify NRPs that potentially contribute to pathogenesis, the 21 predicted NRP synthetases (NRPSs) or NRPS-like proteins of B. bassiana ARSEF 2860 were primarily ranked into three functional groups: basic metabolism (7 NRPSs), pathogenicity (12 NRPSs), and unknown function (2 NRPSs). Based on the transcript levels during in vivo growth on diamondback moth (Plutella xylostella (Linnaeus)), half of the Group II NRPSs were likely to be involved in infection. Given that the metabolites biosynthesized by these NRPSs remain to be determined, our result underlines the importance of the NRPSome in fungal pathogenesis, and will serve as a guide for future genomic mining projects to discover functionally essential and structurally diverse NRPs in fungal genomes.

Curcumin Induces Downregulation of E2F4 Expression and Apoptotic Cell Death in H CT116 Human Colon Cancer Cells; Involvement of Reactive Oxygen Species

  • Kim, Kyung-Chan;Lee, Chu-Hee
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.14 no.6
    • /
    • pp.391-397
    • /
    • 2010
  • E2F transcription factors and their target genes have been known to play an important role in cell growth control. We found that curcumin, a polyphenolic phytochemical isolated from the plant Curcuma longa, markedly suppressed E2F4 expression in HCT116 colon cancer cells. Hydrogen peroxide was also found to decrease E2F4 protein level, indicating the involvement of reactive oxygen species (ROS) in curucmin-induced downregulation of E2F4 expression. Involvement of ROS in E2F4 downregulation in response to curcumin was confirmed by the result that pretreatment of cells with N-acetylcystein (NAC) before exposure of curcumin almost completely blocked the reduction of E2F4 expression at the protein as well as mRNA level. Anti-proliferative effect of curcumin was also suppressed by NAC which is consistent to previous reports showing curcumin-superoxide production and induction of poly (ADP-ribose) polymerase (PARP) cleavage as well as apoptosis. Expression of several genes, cyclin A, p21, and p27, which has been shown to be regulated in E2F4-dependent manner and involved in the cell cycle progression was also affected by curcumin. Moreover, decreased (cyclin A) and increased (p21 and p27) expression of these E2F4 downstream genes by curcumin was restored by pretreatment of cells with NAC and E2F4 overexpression which is induced by doxycycline. In addition, E2F4 overexpression was observed to partially ameliorate curcumin-induced growth inhibition by cell viability assay. Taken together, we found curcumin-induced ROS down-regulation of E2F4 expression and modulation of E2F4 target genes which finally lead to the apoptotic cell death in HCT116 colon cancer cells, suggesting that E2F4 appears to be a novel determinant of curcumin-induced cytotoxicity.

The p90rsk-mediated signaling of ethanol-induced cell proliferation in HepG2 cell line

  • Kim, Han Sang;Kim, Su-Jin;Bae, Jinhyung;Wang, Yiyi;Park, Sun Young;Min, Young Sil;Je, Hyun Dong;Sohn, Uy Dong
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.20 no.6
    • /
    • pp.595-603
    • /
    • 2016
  • Ribosomal S6 kinase is a family of serine/threonine protein kinases involved in the regulation of cell viability. There are two subfamilies of ribosomal s6 kinase, (p90rsk, p70rsk). Especially, p90rsk is known to be an important downstream kinase of p44/42 MAPK. We investigated the role of p90rsk on ethanol-induced cell proliferation of HepG2 cells. HepG2 cells were treated with 10~50 mM of ethanol with or without ERK and p90rsk inhibitors. Cell viability was measured by MTT assay. The expression of pERK1, NHE1 was measured by Western blots. The phosphorylation of p90rsk was measured by ELISA kits. The expression of Bcl-2 was measured by qRT-PCR. When the cells were treated with 10~30 mM of ethanol for 24 hour, it showed significant increase in cell viability versus control group. Besides, 10~30 mM of ethanol induced increased expression of pERK1, p-p90rsk, NHE1 and Bcl-2. Moreover treatment of p90rsk inhibitor attenuated the ethanol-induced increase in cell viability and NHE1 and Bcl-2 expression. In summary, these results suggest that p90rsk, a downstream kinase of ERK, plays a stimulatory role on ethanol-induced hepatocellular carcinoma progression by activating anti-apoptotic factor Bcl-2 and NHE1 known to regulate cell survival.

Alcohol-induced Hyperlipidemia Is Ameliorated by Orally Administered DWP208, a Sodium Succinate Form of ZYM201

  • Cho, Jae Youl;Choi, Jongwon;Park, Jae Gwang;Yi, Young-Su;Hossen, Muhammad Jahangir;Kim, Hyeongmin;Ro, Jieun;Cha, Bae Cheon;Yoo, Eun Sook;Kim, Jong-Hoon;Lee, Jaehwi
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.18 no.6
    • /
    • pp.469-474
    • /
    • 2014
  • DWP208 is a sodium succinate form of ZYM-201 which is a triterpenoid glycoside isolated from Sanguisorba officinalis, a medicinal plant prescribed for various diseases, such as duodenal ulcers and bleeding in East Asian counties. We demonstrated that this compound is able to normalize the altered lipid metabolism induced by hyperglycemia and a high fat diet. In this study, we determined whether hyperlipidemic conditions induced with chronically treated alcohol can also be restored by DWP208. Similar to our previous results, orally administered DWP208 (1 to 10 mg/kg) also ameliorated the hyperlipidemia that was induced by alcohol. This compound reversed the alcohol-induced hyperlipidemia including (i) up-regulated hyperlipidemic parameters such as low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), atherosclerotic index (AI), triglyceride, and total cholesterol, and (ii) down-regulated hyperlipidemic parameters such as absolute body weight, superoxide dismutase (SOD) activity, and high-density lipoprotein (HDL) in serum and liver. According to our data, the ameliorative activity of DWP208 is due to its indirect anti-oxidative activity as a result of which lipid peroxide and hydroxyl radical levels were reduced and the activity of SOD was enhanced. Therefore, our data strongly suggest that DWP208 can be used as a remedy against alcohol-induced hyperlipidemia.

Apoptotic effect of Me fraction of Scutellaria barbata in human leukemic U937 cells (반지련의 Methyl chloride 분획이 U937 단핵 세포 암주의 세포고사에 미치는 영향)

  • Cha Yun Yi;Lee Eun Ok;Lee Ju Ryoung;Kang In Cheol;Park Young Doo;Ahn Kyoo Seok;Kim Sung Hoon
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.17 no.3
    • /
    • pp.629-632
    • /
    • 2003
  • Scutellaria barbata has been used as a traditional Chinese Herb for treating liver, lung and rectal tumors. In the present study, cytotoxic effect of Scutellaria barbata MC fradtion was investigated and it was found to inhibit proliferation of human leukemic U937 cells with an IC50 of approximately 10 μg/ml in a dose-dependent manner. We also demonstrated that Scutellaria barbata MC fraction caused apoptosis in U937 cells. In the flow cytometric assay, the MC fraction-treated U937 cells showed an increase in hypo-diplold Sub G1 DNA contents. DNA fragmentation was observed by TUNEL assay. An increase of Bax:Bcl-2 ratio, activation of caspase-9, caspase-3, and cleavage of poly (ADP-ribose) polymerase (PARP) were demonstrated by western blot analysis. Taken together, these results exerted that the MC fraction suppressed human leukemic U937 cell proliferation by inducing apoptosis via the mitochondrial pathway.

Antioxidant and Anti-inflammatory Effect of Nardostachys Chinensis in IFN-$\gamma$/LPS-stimulated Peritoneal Macrophage (감송향의 in vitro 항산화 및 항염증 효과)

  • Baek, Seol;Choi, Jae-Hyuk;Ko, Sung-Hoon;Lee, Yong-Jae;Cha, Dong-Seok;Park, Eun-Young;Kang, Yang-Gyu;Jeon, Hoon
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.23 no.4
    • /
    • pp.853-859
    • /
    • 2009
  • Nardostachys chinensis has been used widely as a traditional medicine for the treatment of diverse diseases. The dried plant was extracted with 85% methanol extract (NC). We investigated the antioxidant properties of NC on the 1,1-diphenyl-2-picryhydrazyl (DPPH) radical, superoxide anion and nitric oxide radical scavenging capacity under in vitro assays. NC showed potent antioxidant activity, compared to ascorbic acid. In macrophages, nitric oxide is released as an inflammatory mediator and has been proposed to be an important modulator of many pathophysiological conditions in inflammation. In the present study, it was also investigated that the inhibition effects on NO and the mechanism of down-regulation of immune response by NC in IFN-IFN-$\gamma$/LPS-stimulated mouse (C57BL/6) peritoneal macrophages. Extracts of NC suppressed NO production and the expression of iNOS and COX-2. The present results indicate that NC has an antioxidant and anti-inflammatory properties and therefore may be beneficial in diseases which related to oxidative stress-mediated chronic inflammatory disorders.

Effect of different water levels on the photosynthetic pigments of crops

  • Ryu, Hee-La;Jeong, Eun-Ju;Lee, Won-Hee;Lee, In-Jung
    • Proceedings of the Korean Society of Crop Science Conference
    • /
    • 2017.06a
    • /
    • pp.205-205
    • /
    • 2017
  • An excess soil water condition is one of the major problems for the field crops growing in paddy fields because of their poor drainage and less availability for oxygen uptake which leads to adversely affect the photosynthesis. Therefore, the current study was undertaken with aim to investigate the effects groundwater level on the photosynthetic response of soy bean (Urum), red bean (Arari), sesame (Geonbaek), perilla (Dayu) after the transplanting to the lysimeter to investigate the plant-water relation and their effect on photosynthesis. The chlorophyll content of the crops according to the humid conditions of the soy bean, sesame and the perilla was found to be 5%, 6.89 % and 13.7% higher than that of the groundwater treated at 40cm, respectively. On the other hand, the chlorophyll content of adzuki bean decreased 6.6% from the groundwater level of 40cm, and the sorghum decreased by 5.7%. As a result of investigating the Fv / Fm value of groundwater, the adzuki bean at 20cm above groundwater was lower than that of groundwater by 40cm immediately before flowering. The Fv / Fm value of soy bean and sesame at 40cm above groundwater were lowered by flowering under groundwater 20 cm and Fv / Fm value of sorghum is increased at 40 cm treatment immediately before flowering while the Fv / Fm values of the perilla had no significant difference in comparison to those at 20 cm and 40 cm of groundwater. In the case of chlorophyll fluorescence reaction, it is known that the when the absolute value is closer to 0.82, the stress is considered less. As a result of comparing the numerical values of the crops, it was found that the sorghum was the most stressed followed by adzuki bean and sesame, while the soy beans and perilla was found on the average, as they received less stress.

  • PDF

The Ecophysiological Changes of Capsicum annuum on Ozone-Sensitive and Resistant Varieties Exposed to Short-Term Ozone Stress (오존 감수성 및 저항성 고추 품종의 생리생태 변화)

  • Yun, Sung-Chul
    • Korean Journal of Environmental Agriculture
    • /
    • v.23 no.3
    • /
    • pp.128-132
    • /
    • 2004
  • Ozone effects were studied by plant growth chamber to evaluate the impact of ozone ($O_3$) on the physiology of two hot pepper, Capsicum annuum L., cultivars, 'Dabotab' and 'Buchon'. Forty-day old plants with $5{\sim}7$ leaves were exposed to $O_3$ of <20 and 150 nL/L for 8h/d for 3 days. Net photosynthesis and stomatal conductance were measured and foliar injury was described. Foliar damage due to the treated $O_3$ was different from the varieties. 'Dabotab' was most sensitive to $O_3$ and 'Buchon' was resistant. Symptom of ozone damage on the leaves was bifacial necrosis. Decreases of net photosynthesis by $O_3$ were 56% and 40% on 'Dabotab' and 'Buchon', respectively. Decreases of stomatal conductance by $O_3$ were 66% and 63% on each variety. $O_3$ damage on net photosynthesis was started at the low levels of light on the two hot peppers. In addition, assimilation-internal $CO_2$ concentration curves were not different from the two varieties. In conclusion, $O_3$ closed the stomata and decrease net photosynthesis on hot peppers regardless of the ozone sensitivity on leaf injury, but the difference of ecophysiological responses between the two varieties was not found clearly.