• Title/Summary/Keyword: Receptor-mediated

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Functional characterization of a CCCH type zinc-finger protein gene OsZF2 by ectopic overexpression of the gene in rice (과발현 형질전환벼에서 CCCH type zinc-finger protein 유전자 OsZF2 기능 분석)

  • Lee, Jung-Sook;Yoon, In-Sun;Yoon, Ung-Han;Lee, Gang-Seob;Byun, Myung-Ok;Suh, Seok-Chul
    • Journal of Plant Biotechnology
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    • v.36 no.1
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    • pp.23-29
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    • 2009
  • We have previously isolated a CCCH type zinc-finger protein gene, OsZF2 (Oryza sativa Zinc Finger 2), from the cold-treated rice cDNA library. To investigate the potential role of OsZF2, transgenic rice lines over-expressing OsZF2 under the control of CaMV 35S promoter have been developed through Agrobacterium-mediated transformation. Elevated level of OsZF2 transcripts was confirmed by RNA gel blot analysis in transgenic rice. Under the 100 mM NaCl condition, the transgenic rice showed significantly enhanced growth rate in terms of shoot length and fresh weight, implicating that OsZF2 is likely to be involved in salt response of rice. In the field condition, however, the transgenic rice showed a dwarf phenotype and flowering time was delayed. Genome expression profiling analysis of transgenic plants using the 20K NSF rice oligonucleotide array revealed many up-regulated genes related to stress responses and signaling pathways such as chaperone protein dnaJ 72, salt stress-induced protein, PR protein, disease resistance proteins RPM1 and Cf2/Cf5 disease resistance protein, carbohydrate/ sugar transporter, OsWAK kinase, brassinosteroid LRR receptor kinase, and jasmonate O-methyltransferase. These data suggest that the CCCH type zinc-finger protein OsZF2 is a upstream transcriptional factor regulating growth and stress responsiveness of rice.

Prostaglandin E2 Reverses Curcumin-Induced Inhibition of Survival Signal Pathways in Human Colorectal Carcinoma (HCT-15) Cell Lines

  • Shehzad, Adeeb;Islam, Salman Ul;Lee, Jaetae;Lee, Young Sup
    • Molecules and Cells
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    • v.37 no.12
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    • pp.899-906
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    • 2014
  • Prostaglandin $E_2$ ($PGE_2$) promotes tumor-persistent inflammation, frequently resulting in cancer. Curcumin is a diphenolic turmeric that inhibits carcinogenesis and induces apoptosis. $PGE_2$ inhibits curcumin-induced apoptosis; however, the underlying inhibitory mechanisms in colon cancer cells remain unknown. The aim of the present study is to investigate the survival role of $PGE_2$ and whether addition of exogenous $PGE_2$ affects curcumininduced cell death. HCT-15 cells were treated with curcumin and $PGE_2$, and protein expression levels were investigated via Western blot. Reactive oxygen species (ROS) generation, lipid peroxidation, and intracellular glutathione (GSH) levels were confirmed using specific dyes. The nuclear factor-kappa B ($NF-{\kappa}B$) DNA-binding was measured by electrophoretic mobility shift assay (EMSA). $PGE_2$ inhibited curcumin-induced apoptosis by suppressing oxidative stress and degradation of PARP and lamin B. However, exposure of cells to the EP2 receptor antagonist, AH6809, and the PKA inhibitor, H89, before treatment with $PGE_2$ or curcumin abolished the protective effect of $PGE_2$ and enhanced curcumin-induced cell death. $PGE_2$ activates PKA, which is required for cAMP-mediated transcriptional activation of CREB. $PGE_2$ also activated the Ras/Raf/Erk pathway, and pretreatment with PD98059 abolished the protective effect of $PGE_2$. Furthermore, curcumin treatment greatly reduced phosphorylation of CREB, followed by a concomitant reduction of $NF-{\kappa}B$ (p50 and p65) subunit activation. $PGE_2$ markedly activated nuclear translocation of $NF-{\kappa}B$. EMSA confirmed the DNA-binding activities of $NF-{\kappa}B$ subunits. These results suggest that inhibition of curcumin-induced apoptosis by $PGE_2$ through activation of PKA, Ras, and $NF-{\kappa}B$ signaling pathways may provide a molecular basis for the reversal of curcumin-induced colon carcinoma cell death.

The Mechanism for Analgesic Effects of Electroacupuncture on Surgical Ankle Sprain Model Classified as Grade 3 in Rats (수술적 방법으로 유도된 3단계 발목염좌에 대한 전침의 진통기전 연구)

  • Yang, Seung-Bum;Choi, Suck-Jun;Lee, Sung-Ho;Kim, Min-Su;Sohn, In-Chul;Kim, Jae-Hyo
    • Korean Journal of Acupuncture
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    • v.30 no.4
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    • pp.220-229
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    • 2013
  • Objectives : Electroacupuncture(EA) has been used effectively in producing analgesia on ankle sprain pain of humans and animals. Currently to examine the underlying mechanisms of the EA-induced analgesia, the effects of EA on weight-bearing forces(WBR) were examined at ankle sprain classified as grade 3 in rats. Methods : The severe ankle sprain classified as grade 3 was induced surgically by ankle ligament injury in the Sprague-Dawley rats. WBR of the affected foot were examined to evaluate effects and mechanism of EA(2 Hz, 1 ms pulse width, 2 mA intensity, for 15 min) which was applied to either SI6, GB34, or GB39 acupoints. The rats were pretreated with naltrexone(10 mg/kg, i.p.) as an opioid receptor antagonist or phentolamine(5 mg/kg, i.p) as an ${\alpha}$-adrenoceptor antagonist at 30 min before EA. Results : The daily repeat EA at either SI6, GB34, or GB39 showed significant analgesic effects on the severe ankle sprain. Particularly, daily EA at GB34 showed more potent analgesic effect than the others. In addition, the naltrexone pretreatment completely blocked the analgesic effect of EA at GB34, indicating the involvement of the endogenous opioid system in mediating the effect of EA at GB34. However, the phentolamine pretreament blocked analgesic effects of EA at either SI6 or GB39, indicating the involvement of ${\alpha}$-adrenoceptors in mediating the effect of EA at either SI6 or GB39. Conclusions : These data suggest that EA-induced analgesia on ankle sprain pain is mediated through either endogenous opioids or ${\alpha}$-adrenoceptors dependant on acupoint specific pattern.

Effect of Excipients on the Stability and Transport of Recombinant Human Epidermal Growth Factor (rhEGF) across Caco-2 Cell Monolayers

  • Kim, In-Wha;Yoo, Ho-Jung;Song, Im-Sook;Chung, Youn-Bok;Moon, Dong-Cheul;Chung, Suk-Jae;Shim, Chang-Koo
    • Archives of Pharmacal Research
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    • v.26 no.4
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    • pp.330-337
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    • 2003
  • The effect of sixteen excipients on the transport of recombinant human epidermal growth factor (rhEGF) across Caco-2 cell monolayers was examined at $37^{\circ}C$. The apparent apical to basolateral (A-B) permeability ($P_{app}$) of 30 $\mu$ M rhEGF was $8.15\times 10^{-7}$ cm/sec, indicative of a poor level of absorption in the GI tract. The Papp was 1.7- and 6.3-fold greater than the $P_{app}$ in the basolateral to apical (B-A) direction and the A-B permeability of mannitol, respectively, and decreased dramatically to a negligible level at $4^{\circ}C$, consistent with a receptor mediated transcytosis of rhEGF. The stability of rhEGF was very poor, undergoing more than 85% degradation in 2 h in the transport medium at $37^{\circ}C$. A significant increase in the $P_{app}$ could be achieved by the addition of certain excipients, as exemplified by 23, 21, 20 and 16-fold increases, in the presence of sodium taurochenodeoxycholate (NaTCDC), sodium taurodeoxycholate (NaTDC), sodium glycodeoxycholate (NaGDC) and sodium laurylsulfate (SLS) (all at a concentration of 1 % w/v), respectively. A significant increase in stability could also be achieved by the addition of some of the excipients, as represented by 1 % SLS, which nearly completely stabilized the rhEGF. Unfortunately, however, an increase in the $P_{app}$ of rhEGF could not be achieved without a simultaneous and extensive decrease in the integrity of the cell membranes. Thus, more efficient excipients, that specifically enhance the permeation of rhEGF and do not alter the membrane integrity, should be pursued in order to safely enhance the permeation of rhEGF.

Gintonin absorption in intestinal model systems

  • Lee, Byung-Hwan;Choi, Sun-Hye;Kim, Hyeon-Joong;Park, Sang-Deuk;Rhim, Hyewhon;Kim, Hyoung-Chun;Hwang, Sung-Hee;Nah, Seung-Yeol
    • Journal of Ginseng Research
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    • v.42 no.1
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    • pp.35-41
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    • 2018
  • Background: Recently, we identified a novel ginseng-derived lysophosphatidic acid receptor ligand, called gintonin. We showed that gintonin induces $[Ca^{2+}]i$ transient-mediated morphological changes, proliferation, and migration in cells expressing lysophosphatidic acid receptors and that oral administration of gintonin exhibits anti-Alzheimer disease effects in model mice. However, little is known about the intestinal absorption of gintonin. The aim of this study was to investigate gintonin absorption using two model systems. Methods: Gintonin membrane permeation was examined using a parallel artificial membrane permeation assay, and gintonin absorption was evaluated in a mouse everted intestinal sac model. Results: The parallel artificial membrane permeation assay showed that gintonin could permeate an artificial membrane in a dose-dependent manner. In the everted sac model, gintonin absorption increased with incubation time (from 0 min to 60 min), followed by a decrease in absorption. Gintonin absorption into everted sacs was also dose dependent, with a nonlinear correlation between gintonin absorption and concentration at 0.1-3 mg/mL and saturation at 3-5 mg/mL. Gintonin absorption was inhibited by the Rho kinase inhibitor Y-27632 and the sodiumeglucose transporter inhibitor phloridzin. Moreover, lipid extraction with methanol also attenuated gintonin absorption, suggesting the importance of the lipid portion of gintonin in absorption. This result shows that gintonin might be absorbed through passive diffusion, paracellular, and active transport pathways. Conclusion: The present study shows that gintonin could be absorbed in the intestine through transcellular and paracellular diffusion, and active transport. In addition, the lipid component of gintonin might play a key role in its intestinal absorption.

Local Expression of $Mel_{la}$ and Effect of Melatonin on Expression of PLP-A Gene in the Rat Placenta (흰쥐 태반에서의 $Mel_{la}$ 유전자 발현과 멜라토닌이 PLP-A 유전자 발현에 미치는 영향)

  • Shin, Chang-Sook;Lee, Chae-Kwan;Kang, Han-Seung;Kim, Haekwon;Yoon, Yong-Dal;Moon, Deog-Hwan;Kang, Sung-Goo
    • Development and Reproduction
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    • v.5 no.2
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    • pp.181-187
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    • 2001
  • Seasonal changes and circadian rhythm of plasma prolactin(PRL) concentration in mammals are mediated by melatonin. Pinealectomy or denervation of the pineal gland produces an increase in plasma PRL level. In the rat placenta several members of the PRL family gene are expressed during the late pregnancy. However, the full spectrum of their expression mechanisms and regulatory factors are not elucidated yet. Present study aimed to investigate the local expression of the melatonin receptor la(Me $l_{la}$ ) gene and the effect of melatonin on expression of prolactin-like protein A(PLP-A), a member of the PRL-family gene in the rat placenta. According to the RT-PCR, northern blot and in situ hybridization experiments, Me $l_{la}$ gene was locally expressed in the rat placenta, Me $l_{la}$ mRNA was localized mainly in the placental junctional and labyrinth zones. Interestingly, junctional zone of the placenta showed strong expression of Me $l_{la}$ at daytime(16:00) than at nighttime(22:00). Melatonin agonist, chlorornelatonin decreased the PLP-A mRNA levels in the rat placenta. These results suggest that melatonin coupled with Me $l_{la}$ , may act as a regulation factor that mediates the expression of the PLP-A gene in the rat placenta.

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Tumorigenic Effects of Endocrine-Disrupting Chemicals are Alleviated by Licorice (Glycyrrhiza glabra) Root Extract through Suppression of AhR Expression in Mammalian Cells

  • Chu, Xiao Ting;Cruz, Joseph Dela;Hwang, Seong Gu;Hong, Heeok
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.13
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    • pp.5117-5121
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    • 2014
  • Endocrine-disrupting chemicals (EDCs) have been reported to interfere with estrogen signaling. Exposure to these chemicals decreases the immune response and causes a wide range of diseases in animals and humans. Recently, many studies showed that licorice (Glycyrrhiza glabra) root extract (LRE) commonly called "gamcho" in Korea exhibits antioxidative, chemoprotective, and detoxifying properties. This study aimed to investigate the mechanism of action of LRE and to determine if and how LRE can alleviate the toxicity of EDCs. LRE was prepared by vacuum evaporation and freeze-drying after homogenization of licorice root powder that was soaked in 80% ethanol for 72 h. We used 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as an EDC, which is known to induce tumors or cancers; MCF-7 breast cancer cells were used as a tumorigenic model. These were treated with TCDD and various concentrations of LRE (0, 50, 100, 200, $400{\mu}g/mL$) for 24, 48, and 72 h. As a result, TCDD stimulated MCF-7 cell proliferation, but LRE significantly inhibited TCDD-induced MCF-7 cell proliferation in a dose- and time-dependent manner. Expression of TCDD toxicity-related genes, i.e., aryl hydrocarbon receptor (AhR), AhR nuclear translocator, and cytochrome P450 1A1, were subsequently down-regulated by LRE in a dose-dependent manner. Analysis of cell cycle distribution after treatment of MCF-7 cells with TCDD and various concentrations of LRE showed that LRE inhibited the proliferation of MCF-7 cells via G2/M phase arrest. Reverse transcription-polymerase chain reaction and Western blot analyses also revealed that LRE dose-dependently increased the expression of the tumor suppressor genes p53 and p27 and down-regulated the expression of cell cycle-related genes. These data suggest that LRE can mitigate the tumorigenic effects of TCDD in breast cancer cells by suppression of AhR expression and cell cycle arrest. Thus, LRE can be used as a potential toxicity-alleviating agent against EDC-mediated disease.

Semaphoring mAb: a New Guide in RIT in Inhibiting the Proliferation of Human Skin Carcinoma

  • Liu, Yuan;Ma, Jing-Yue;Luo, Su-Ju;Sun, Chen-Wei;Shao, Li-Li;Liu, Quan-Zhong
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.3
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    • pp.941-945
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    • 2015
  • Semaphoring is a transmembrane receptor which participates in many cytokine-mediated signal pathways that are closely related to the angiogenesis, occurrence and development of carcinoma. The present study was designed to access the effect of mono-antibody (mAb) guided radioimmunotherapy (RIT) on skin carcinoma and investigate the potential mechanisms. Semaphoring mAb was acquired from mice (Balb/c), purified with rProtein A column; purity, concentration and activity were tested with SDS-PAGE and indirect ELISA; specificity and expression on the cutanuem carcinoma line and tissue were tested by Western blotting; morphology change was assessed by microscopy. MTT assay and colony inhibition tests were carried out to test the influence on the proliferation of tumor cells; Western blotting was also carried out for expression of apoptosis-associated (caspase-3, Bax, Bcl-2) and proliferation-related (PI3K, p-Akt, Akt, p-ERK1/2, ERK1/2) proteins and analyse the change in signal pathways (PI3K/Akt and MEK/ERK). The purity of purified semaphorin mAb was 96.5% and the titer is about $1{\times}10^6$. Western blotting showed semaphoring mAb to have specifically binding stripes with semaphoring b1b2 protein, B16F10, and A431 cells at 39KDa, 100KDa and 130KDa, respectively. Positive expression was detected both in cutanuem carcinoma line and tissue and it mostly located in cell membranes. MMT assay revealed dose-relate and time-relate inhibitory effect of semaphorin mAb on A431 and B16F10. Colony inhibition tests also showed dose-relate inhibitory effects. Western blotting demonstrated the expression of apoptosis and proliferation-related protein and changes in signal pathway. In conclusion, we demonstrated that semaphorin is highly expressed on the tumor cell-surfaces and RIT with semaphorin mAb has effect in i nhibiting proliferation and accelerating apoptosis of tumor cells.

Effect of Acacia catechu Extract on 3T3-L1 Preadipocyte Differentiation (지방세포의 분화에 미치는 Acacia catechu 추출물의 항비만 효과)

  • Kim, Dong-Gyu;Kang, Min Jung;Suh, Hwa Jin;Kwon, Oh Oun;Shin, Jung Hye
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.8
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    • pp.1107-1113
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    • 2016
  • The purpose of this study was to investigate the effects of catechu water extract on adipogenesis in 3T3-L1 adipocytes. 3T3-L1 preadipocytes were differentiated with adipogenic regents by incubation for 9 days in the absence or presence of catechu extract ranging from $1{\sim}200{\mu}g/mL$. The effect of catechu extracts on cell proliferation of 3T3-L1 preadipocytes was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The effect of catechu extracts on 3T3-L1 differentiation was examined by measuring intracellular lipid droplet and triglyceride contents. These results were obtained from preadipocyte proliferation and adipocyte differentiation of 3T3-L1. Catechu extracts inhibited lipid accumulation and remarkably decreased triglyceride contents in 3T3-L1 preadipocytes at a concentration showing no cytotoxicity. The anti-adipogenic effects of catechu appeared to be mediated by significant down-regulation of expression of peroxisome proliferator-activated receptor ${\gamma}$, CCAAT/enhancer-binding protein ${\alpha}$, and sterol regulatory element-binding protein 1c proteins apart from expression of hormone-sensitive lipase. We suggest that catechu extracts significantly inhibit adipogenesis and can be used for regulation of obesity.

Association between Laryngeal Squamous Cell Carcinoma and Polymorphisms in Tumor Necrosis Factor Related Apoptosis Induce Ligand (TRAIL), TRAIL Receptor and sTRAIL Levels

  • Verim, Aysegul;Turan, Saime;Farooqi, Ammad Ahmad;Kahraman, Ozlem Timirci;Tepe-Karaca, Cigdem;Yildiz, Yemliha;Naiboglu, Baris;Ozkan, Nazli Ezgi;Ergen, Arzu;Isitmangil, Gulbu Aydinoglu;Yaylim, Ilhan
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.24
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    • pp.10697-10703
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    • 2015
  • The laryngeal squamous cell carcinoma (LSCC) is one of the most common malignant tumors occurring in the head and neck. Tumor necrosis factor related apoptosis induce ligand (TRAIL) and TRAIL-receptors (DR4, DR5, DcR1, DcR2) are known as important members of TRAIL-mediated biochemical signaling pathway. Associations between polymorphisms in these genes and clinicopathological characteristics of human laryngeal carcinoma are not well defined. This study therefore aimed to investigate a possible relationship among the TRAIL and TRAIL-DR4 polymorphisms and sTRAIL levels in the risk or progression of LSCC. A total of 99 patients with laryngeal cancer and 120 healthy subjects were enrolled in the study. DR4 C626G and TRAIL 1595 C/T genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis and sTRAIL levels were measured by ELISA. There were significant differences in the distribution of DR4 C626G genotypes and frequencies of the alleles between laryngeal cancer patients and controls (p<0.001) but not in TRAIL 1595 C/T. We found the increased frequency of the DR4 C626G homozygote CC genotype in patients than in controls (p<0.001). Haplotype analysis revealed that there was also a statistically significant relationship between TRAIL and TRAIL-DR4 polymorphisms and laryngeal cancer. Serum sTRAIL levels in the laryngeal patients with CC genotype who had advanced tumour stage were lower than those of patients with early tumor stage (p=0.014). Our findings suggest that DR4 C626G genotypes and sTRAIL levels might be associated with progression of laryngeal cancer in the Turkish population.