• Food Science and Biotechnology
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• v.18 no.6
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• pp.1500-1504
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• 2009

Effects of methanol extract from turmeric (Curcuma longa L.) (CME) on underlying mechanisms of lipolysis were investigated in 3T3-L1 adipocytes. Compared to the control, lipid accumulation with 72 hr treatment of CME at the concentration $20\;{\mu}g/mL$ was significantly decreased by 19.9% as quantified by Oil red O dye. Intracellular triglyceride (TG) content was also lowered by 19.3%. To determine the mechanism for TG content reduction, glycerol release level was measured. Incubation of 3T3-L1 adipocytes with 15 and $20\;{\mu}g/mL$ of CME significantly elevated the level of free glycerol released into the cultured medium by 20.4 and 28.6%, respectively. In subsequent measurements using quantitative real-time polymerase chain reaction (PCR), mRNA levels of hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL) were significantly increased by 21.2 and 24.9%, respectively, at the concentration $20\;{\mu}g/mL$. Results indicated that CME stimulated lipolysis through induction of HSL and ATGL mRNA expressions, resulting in increased glycerol release.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7719-7724
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• 2013

Background: Overexpression of survivin, a known inhibitor of apoptosis, is associated with tumor progression and drug resistance in numerous malignancies, including leukemias. The aim of this study was to investigate the effect of a specific survivin small interference RNA (siRNA) on proliferation and the sensitivity of HL-60 acute myeloid leukemia (AML) cells to the chemotherapeutic drug etoposide. Materials and Methods: The cells were transfected with siRNAs using Lipofectamine $^{TM}2000$ transfection reagent. Relative survivin mRNA and protein levels were measured by quantitative real-time PCR and Western blotting, respectively. Trypan blue exclusion assays were performed to monitor tumor cell proliferation after siRNA transfection. The cytotoxic effects of etoposide and survivin siRNA, alone and in combination, on leukemic cells were determined using MTT assay. Apoptosis was assessed by ELISA cell death assay. Results: Survivin siRNA markedly reduced both mRNA and protein expression levels in a time-dependent manner, leading to distinct inhibition of cell proliferation and increased spontaneous apoptosis. Surprisingly, survivin siRNA synergistically increased the cell toxic effects of etoposide. Moreover, survivin down-regulation significantly enhanced its induction of apoptosis. Conclusions: Our study suggests that down-regulation of survivin by siRNA can trigger apoptosis and overcome drug resistance of leukemia cells. Therefore, survivin siRNA may be an effective adjuvant in AML chemotherapy.

• Archives of Pharmacal Research
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• v.25 no.2
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• pp.197-201
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• 2002

${\beta}-lonone$ has been reported to induce the cytochrome P45O (P45O) 2B1 in rats. In this study, the effects of ${\beta}-ionone$ and an isomer, ${\alpha}-ionone$, on liver P45O IA and 2B expression in Sprague Dawley rats were investigated . Subcutaneous administration of ${\alpha}-$ and ${\beta}-lonone$ 72 and 48hr prior to sacrificing the animals induced the liver microsomal P45O 1A and 2B proteins. P45O 2Bl induction was associated with the accumulation of its corresponding mRNA. 1 Induction by ${\beta}-lonone$ was much higher than that by ${\alpha}-ionone$-ionone in both the mRNA and protein levels. When the route of administration was compared, P45O 2B was induced more strongly after oral administration compared to that after subcutaneous injection. A single oral dose of 100, 300 and 600 mg/kg of ${\alpha}-$ and ${\beta}-lonone$ for 24 h induced P45O 2B1 -selective pentoxyresorufin Odepentylase activity comparably in a dose-dependent manner In addition, ${\alpha}-$ and ${\beta}-lonone$ induced the P45O 1A and 2B proteins. These results suggest that ${\alpha}-$ and ${\beta}-lonone$ might be potent P45O 2Bl inducers in rats, and that both ionones may be useful for examining the role of metabolic activation in chemical-induced toxicity where metabolic activation is required.

• Biomolecules & Therapeutics
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• v.7 no.1
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• pp.22-28
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• 1999

Induction of apoptosis is considered to be the underlying mechanism that accounts for the efficiency of chemotherapeutic drugs. It has recently been proposed that doxorubicin (DOX) can induce apoptosis in human leukemic cells via the Fas/Fas Ligand (FasL) system. Comparison of Fas and FasL mRNA expression between drug- and anti-Fas antibody(Fas-Ab)- induced apoptosis was analyzed for examining the role of Fas/FasL system in the mediation of drug-induced apoptosis. After HL-60 cells were routinely cultured, MTT assay was performed for cytotoxicity test. Giemsa staining was carried out to monitor the apoptosis morphologically. By semiquantitative RT-PCR analysis, the expression of Fas and FasL at 4, 10, 24 hours was determined after DOX and Fas-Ab treatment. Dose-dependent cytotoxicity was induced by DOX-treatment, while Fas-Ab treatment showed the similar dose-dependent pattern but the cytotoxicity is not reached at LD$_{50}$ at 100 ng/ml concentration of Fas-Ab. In the 10ng/m1 DOX and 10ng/m1 Fas-Ab treated group, typical apoptotic cell morphology was shown such as fragmented nuclei and cell membrane budding in the Giemsa-stained slide. Fas mRNA expression was not changed significantly in the both groups. But, FasL mRNA expression was induced significantly at initial period of apoptosis. In this study, Fas/FasL interaction assumed to be involved in drug-induced apoptosis.s.

• Toxicological Research
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• v.6 no.1
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• pp.89-97
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• 1990

Neural regulation of phenylethanolamine N-meth-yltransferase (PNMT) was studied with reserpine as a neuronal agent in rat adrenal medulla. The enzyme activity assay and northern blot analysis were performed to determine whether the induction of PNMT activity after reserpine treatment was associated with elevation of mRNA coding for PNMT. The i.p. administration of reserpine (2.5 mg/kg) on alternate days fot 4 injections to rats brought about 30% increase of adrenal medullary PNMT activity and approximately 60% stimulation of the PNMT mRNA level in rat adrenal gland. A dose of 10 mg/kg of reserpine was chosen to perform optimum induction of PNMT activity in the rat adrenal gland based on the results of dose response curve of reserpine. Time course reserpine (10 mg/kg) effects on the rat adrenal medullary PNMT were as follows: 1. Peripheral PNMT activity reached maximum level after 7 days of drug treatment on alternate days. 2. Trans-synaptic stimulation by reserpine increased pretranslational activity of rat adrenal PNMT, but not translational activity. 3. Immunotitration of PNMT molecule after reserpine treatment indicated that reserpine produced an enzyme with greater antibody affinity than endogenous molecule in the rat adrenal gland.

• International Journal of Oral Biology
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• v.31 no.1
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• pp.21-26
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• 2006

Periodontopathogens including Porphyromonas gingivalis interact with host periodontal cells and the excessive subsequent host responses contribute a major part to the development of periodontal diseases. Cyclooxygenase(COX)-2-synthesized $PGE_2$ has detrimental activities in terms of periodontal pathogenesis. The present study investigated induction of COX-2 expression by P. gingivalis in human monocytic THP-1 cells. Live P. gingivalis increased expression of COX-2, but not that of COX-1, which was demonstrated at both mRNA and protein levels. Elevated levels of $PGE_2$ were released from P. gingivalis-infected THP-1 cells. Pharma-cological inhibition of p38 mitogen-activated protein kinase(MAPK) and extracellular signal-regulated kinase(ERK) substantially attenuated P. gingivalis-induced COX-2 mRNA expression. Indeed, activation of p38 MAPK and ERK was observed in P. gingivalis-infected THP-1 cells. Also, P. gingivalis induced activation of nuclear $factor-{\kappa}B\;(NF-{\kappa}B)$ which is an important transcription factor for COX-2. These results suggest that COX-2 expression is up regulated in P. gingivalis-infected monocytic cells, at least in part, via p38 MAPK, ERK, and $NF-{\kappa}B$.

• Korean Journal of Biological Psychiatry
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• v.3 no.1
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• pp.115-120
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• 1996

To investigate characteristic drug effects on the genetic basis, the authors administered haloperidol- the $D_2$ antagonist- and clozapine -the atypical antipsychotics with few extra- pyramidal side effects- to the rats. Then, we edobtain brain specimen from the striatum, prefrontal cortex, and cortical region and compared the degree of c-fos expression. The results are 1) haloperidol was found to produce a rapid and transient induction of dos mRNA expression in striatum as compared with cortex and prefrontal area. 2) clozapine was found to produce rapid induction of c-fos mRNA in striatum and prefrontal area. From these data, we can concluded that the mechanism of action of haloperidol is different from the mechanism of clozapine in gene expression.

• Journal of Cancer Prevention
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• v.21 no.3
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• pp.135-143
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• 2016

Background: Fraxetin (7,8-dihydroxy-6-methoxy coumarin), a coumarin derivative, has been reported to possess antioxidative, anti-inflammatory and neuroprotective effects. A number of recent observations suggest that the induction of heme oxygenase-1 (HO-1) inhibits inflammation and tumorigenesis. In the present study, we determined the effect of fraxetin on HO-1 expression in HaCaT human keratinocytes and investigated its underlying molecular mechanisms. Methods: Reverse transcriptase-PCR and Western blot analysis were performed to detect HO-1 mRNA and protein expression, respectively. Cell viability was measured by the MTS test. The induction of intracellular reactive oxygen species (ROS) by fraxetin was evaluated by 2′,7′-dichlorofluorescin diacetate staining. Results: Fraxetin upregulated mRNA and protein expression of HO-1. Incubation with fraxetin induced the localization of nuclear factor-erythroid-2-related factor-2 (Nrf2) in the nucleus and increased the antioxidant response element-reporter gene activity. Fraxetin also induced the phosphorylation of Akt and AMP-activated protein kinase $(AMPK){\alpha}$ and diminished the expression of phosphatase and tensin homolog, a negative regulator of Akt. Pharmacological inhibition of Akt and $AMPK{\alpha}$ abrogated fraxetin-induced expression of HO-1 and nuclear localization of Nrf2. Furthermore, fraxetin generated ROS in a concentration-dependent manner. Conclusions: Fraxetin induces HO-1 expression through activation of Akt/Nrf2 or $AMPK{\alpha}/Nrf2$ pathway in HaCaT cells.

• Molecules and Cells
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• v.42 no.10
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• pp.721-728
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• 2019

Non-structural protein 1 (NS1) of influenza virus has been shown to inhibit the innate immune response by blocking the induction of interferon (IFN). In this study, we isolated two single-stranded RNA aptamers specific to NS1 with $K_d$ values of $1.62{\pm}0.30nM$ and $1.97{\pm}0.27nM$, respectively, using a systematic evolution of ligand by exponential enrichment (SELEX) procedure. The selected aptamers were able to inhibit the interaction of NS1 with tripartite motif-containing protein 25 (TRIM25), and suppression of NS1 enabled retinoic acid inducible gene I (RIG-I) to be ubiquitinated regularly by TRIM25. Additional luciferase reporter assay and quantitative real-time PCR (RT-PCR) experiments demonstrated that suppression of NS1 by the selected aptamers induced IFN production. It is noted that viral replication was also inhibited through IFN induction in the presence of the selected aptamers. These results suggest that the isolated aptamers are strongly expected to be new therapeutic agents against influenza infection.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.703-712
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• 2016

Monoclonal antibodies with specific antigens have been widely used as targeted therapy for cancer. Hep88 mAb is a monoclonal antibody which shows specific binding with anti-cancer effects against the HepG2 cell line. However, its mechanisms of action are still not completely understood. We examined cell cycling and apoptosis by flow cytometry and mRNA expression of factors involved in apoptosis and paraptosis in Hep88 mAb-treated HepG2 cells by real-time PCR. The cell-cycle analysis demonstrated that growth-inhibitory activity was associated with G2/M cell cycle arrest. Hep88 mAb induced a significant increase in apoptotic cell populations in a dose- and time-dependent manner. The mRNA expression results also suggested that the process triggered by Hep88 mAb involved up-regulation of tumor suppressor p53, pro-apoptotic Bax, Cathepsin B, Caspase-3 and Caspase-9, with a decrease of anti-apoptotic Bcl-2 - thus confirming paraptosis and apoptosis programmed cell death. These findings represent new insights into the molecular mechanisms underlying the anti-cancer properties of Hep88 mAb in liver cancer cells.