• The Korean Journal of Pharmacology
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• v.29 no.1
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• pp.97-105
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• 1993

Adenosine receptors in rat adipose tissues have been reported to be of $A_{1}$ subclass, and their stimulation leads to inhibition of adenylyl cyclase, resulting in inhibition of lipolysis. In the present study we investigated changes in $A_{1}$ adenosine receptor-adenylyl cyclase system of adipocytes following induction of experimental diabetes in rats. One week following experimental diabetes were induced by intravenous injection of streptozotocin (50 mg/kg body wt.), adipocytes from rats $(170{\sim}230g)$ fed ad libitum were isolated using collagenase. When adipocytes were incubated for 1 h with 1 unit/ml adenosine deaminase and $1\;{\mu}M$ isoproterenol, and assayed for glycerol formation, it was found that the inhibition of lipolysis in diabetic adipocytes by $(-)-N^{6}-(R-phenylisopropyl)adenosine$ (PIA), an $A_{1}$, adenosine receptor agonist, was twice that of control adipocytes. In an effort to delineate the mechanism(s), $[^{3}H]PIA$ binding to adipocytic membranes from diabetic and control rats were determined. Neither the affinities nor numbers of $A_{1}$ adenosine receptor were significantly different from each other (Best fit parameters for the one-site model are: $K_{d}=0.51{\pm}0.09nM$ and $B_{max}=1.60{\pm}0.12\;pmoles/mg$ protein for control membranes; $K_{d}=0.54{\pm}0.21\;nM$ and $B_{max}=1.72{\pm}0.31\;pmoles/mg$ protein for diabetic membranes). However, the inhibiton by PIA of the isoproterenol-stimulated adenylyl cyclase activities was found to be 1.9 times higher in adipocytic membranes from diabetic rats than those from controls. These results suggest that the increased sensitivity of inhibition of lipolysis to PIA in adipocytic membranes from diabetic rats is due to changes in signal transduction pathways, rather than alterations of $A_{1}4 adenosine receptor molecules themselves.

• Journal of Ginseng Research
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• v.41 no.3
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• pp.257-267
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• 2017

Background: Heat-processed ginseng, sun ginseng (SG), has been reported to have improved therapeutic properties compared with raw forms, such as increased antidiabetic, anti-inflammatory, and antihyperglycemic effects. The aim of this study was to investigate the antiobesity effects of SG through the suppression of cell differentiation and proliferation of mouse 3T3-L1 preadipocyte cells and the lipid accumulation in Caenorhabditis elegans. Methods: To investigate the effect of SG on adipocyte differentiation, levels of stained intracellular lipid droplets were quantified by measuring the oil red O signal in the lipid extracts of cells on differentiation Day 7. To study the effect of SG on fat accumulation in C. elegans, L4 stage worms were cultured on an Escherichia coli OP50 diet supplemented with $10{\mu}g/mL$ of SG, followed by Nile red staining. To determine the effect of SG on gene expression of lipid and glucose metabolism-regulation molecules, messenger RNA (mRNA) levels of genes were analyzed by real-time reverse transcription-polymerase chain reaction analysis. In addition, the phosphorylation of Akt was examined by Western blotting. Results: SG suppressed the differentiation of 3T3-L1 cells stimulated by a mixture of 3-isobutyl-1-methylxanthine, dexamethasone, and insulin (MDI), and inhibited the proliferation of adipocytes during differentiation. Treatment of C. elegans with SG showed reductions in lipid accumulation by Nile red staining, thus directly demonstrating an antiobesity effect for SG. Furthermore, SG treatment down-regulated mRNA and protein expression levels of peroxisome proliferator-activated receptor subtype ${\gamma}$ ($PPAR{\gamma}$) and CCAAT/enhancer-binding protein-alpha ($C/EBP{\alpha}$) and decreased the mRNA level of sterol regulatory element-binding protein 1c in MDI-treated adipocytes in a dose-dependent manner. In differentiated 3T3-L1 cells, mRNA expression levels of lipid metabolism-regulating factors, such as amplifying mouse fatty acid-binding protein 2, leptin, lipoprotein lipase, fatty acid transporter protein 1, fatty acid synthase, and 3-hydroxy-3-methylglutaryl coenzyme A reductase, were increased, whereas that of the lipolytic enzyme carnitine palmitoyltransferase-1 was decreased. Our data demonstrate that SG inversely regulated the expression of these genes in differentiated adipocytes. SG induced increases in the mRNA expression of glycolytic enzymes such as glucokinase and pyruvate kinase, and a decrease in the mRNA level of the glycogenic enzyme phosphoenol pyruvate carboxylase. In addition, mRNA levels of the glucose transporters GLUT1, GLUT4, and insulin receptor substrate-1 were elevated by MDI stimulation, whereas SG dose-dependently inhibited the expression of these genes in differentiated adipocytes. SG also inhibited the phosphorylation of Akt (Ser473) at an early phase of MDI stimulation. Intracellular nitric oxide (NO) production and endothelial nitric oxide synthase mRNA levels were markedly decreased by MDI stimulation and recovered by SG treatment of adipocytes. Conclusion: Our results suggest that SG effectively inhibits adipocyte proliferation and differentiation through the downregulation of $PPAR{\gamma}$ and $C/EBP{\alpha}$, by suppressing Akt (Ser473) phosphorylation and enhancing NO production. These results provide strong evidence to support the development of SG for antiobesity treatment.

• Journal of Life Science
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• v.23 no.11
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• pp.1397-1403
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• 2013

Fructus Sophorae, the dried ripe fruit of Styphnolobium japonicum (L.), is an herbal ingredient used in traditional Oriental medicine. This study was carried out to investigate the effects of Fructus Sophorae extracts (FSE) on immune modulation in a murine RAW 264.7 macrophage model. As immune response parameters, the production of prostaglandin $E_2$ ($PGE_2$) and tumor necrotic $factor-{\alpha}$ ($TNF-{\alpha}$) were evaluated. Our data revealed that FSE increased the macrophage activation and the production of $PGE_2$ and $TNF-{\alpha}$, which was consistently correlated with upregulation of cyclooxygenase-2 (COX-2) and $TNF-{\alpha}$ expression at both transcriptional and translational levels. On comparative cytokine protein array, FSE significantly increased several cytokines, which was associated with phosphorylation of mitogen- activated protein kinases (MAPKs), including extracellular signal-regulated kinase (ERK), p38 MAPK and c-Jun N-terminal kinase (JNK), and Akt in RAW 264.7 cells. However, each inhibitor of these molecules attenuated the FSE-induced $PGE_2$ production. These results indicate that FSE activated macrophages through the activation of MAPKs and phosphatidylinositol-3-kinase (PI3K)/Akt signaling pathways in RAW 264.7 macrophages. These findings suggest that FSE may provide a promising source of an immunoenhancing agent.

• Journal of Radiation Industry
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• v.7 no.1
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• pp.7-14
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• 2013

In this study, we investigated the applicability of the photostimulated luminescence (PSL), thermoluminescence (TL) and electron spin resonance (ESR) methods for various foods. The analysed samples consist of 11 items including dried fruits (6 items) and mushrooms (5 items). To compare between non-irradiated and irradiated food, all samples were irradiated with $^{60}Co$ gamma-ray source. In PSL study, the photon counts of all the unirradiated sample were identified negative (lower than 700). The photon counts irradiated (1, 5, 10 kGy) dried date-palm, dried jujube and mushrooms (Auricularia auricula, Phellinus linteus and Sarcodon aspratus) showed positive (higher than 5,000) and the results for the other samples were negative or intermediate (>700 and >5,000). In TL analysis most of items can be applicable to detect irradiated foods because of showing TL ratio above 0.1. The glow curves by TL method were estimated in the range of $150{\sim}250^{\circ}C$ in irradiated samples. In ESR measurements, the intensity of ESR signal (single-line) increased as the dose of irradiation increased. In particular, the specific ESR signals of irradiation-induced radical were detected in dried papaya, dried date-palm, dried banana, dried pineapple and S. aspratus. According to the results, PSL, TL and ESR methods were successfully applied to detect the irradiated foods. It is concluded that PSL, TL and ESR methods are suitable for detection of irradiated samples and a combined method is recommendable for enhancing the reliability of detection results.

• Journal of Radiation Industry
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• v.7 no.1
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• pp.69-74
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• 2013

This study examined radiation detection characteristics of spices (cumin, caper and turmeric), other small fruits (hut-gae berry and boxthorn), and pollen extract product. Each samples were irradiated at dose of 1, 5, and 10 kGy and analyzed by the thermoluminescence (TL) and electron spin resonance (ESR) methods. To compare between non-irradiated and irradiated food, all samples were irradiated with $^{60}Co$ gamma-ray source. In TL analysis, most of samples could be applied to detect irradiated foods because of showing TL ratio above 0.1. The glow curves examined by TL method were estimated in the range of $150{\sim}250^{\circ}C$ in irradiated samples. In ESR measurements, the intensity of ESR signal (single-line) increased as the increase of irradiation dose. In particular, the specific ESR signals of irradiation-induced radical were detected in hut-gae berry and pollen extract product. As a results, it is considered that TL and ESR methods can be used to detect both hut-gae berry and pollen extract product. But cumin, caper, turmeric and boxthorn irradiated with gamma ray could be detected only by TL method. It is concluded that TL and ESR methods are suitable for detection of irradiated samples and a combined method is recommendable for enhancing the reliability of detection results.

• Journal of Food Hygiene and Safety
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• v.34 no.5
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• pp.495-501
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• 2019

Aloin [1,8-Dihydroxy-10-(${\beta}$-D-glucopyranosyl)-3-(hydroxymethyl)-9(10H)-anthracenone], is a natural anthraquinone from aloe. It has been shown to have antioxidant and anticancer effects in various types of human cancer cells, but the anticancer effects of aloin in human colorectal cancer cells HT-29 have not been elucidated. In this study, possible mechanisms by which aloin exerts its apoptotic action in cultured human colorectal cancer HT-29 cells were investigated. The results of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay shows that treatment with aloin (0, 100, 200, 300 and $400{\mu}M$) reduced cell viability in a concentration-dependent manner in HT-29 and showed no effects on cell proliferation in A375SM and AGS cells. In addition, it was confirmed that apoptotic body was significantly increased as shown by 4',6-diamidino-2-phenylindole (DAPI) staining, and increased apoptosis rate by flow cytometry in HT-29 cells treated with aloin (0, 200 and $400{\mu}M$). We confirmed by western blotting that aloin activated Bax (pro-apoptotic), cleaved-poly (ADP-ribose) polymerase (PARP) and caspase-3, -8 and Bcl-2 (anti-apoptotic) were not changed compared with the control. Aloin induced up-regulation of phospho-p38 and down-regulation of phospho-extracellular signal-regulated kinase (ERK)1/2. Therefore, aloin suppressed the growth inhibitory effects by the induction of apoptosis in human colorectal cancer cells and has potential as a cancer preventive medicine.

• Journal of Life Science
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• v.31 no.9
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• pp.827-833
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• 2021

Dendropanax morbiferus leaves (DPL) has been used as a medicine since ancient times in various diseases such as inflammation, diabetes, and cancer. In particular, it has been found to have anticancer effects on several types of cancer cells, but the anticancer effect on breast cancer cells SK-BR-3 has not yet been revealed. Therefore, in this study, DPL caused proliferation inhibition in breast cancer cells SK-BR-3 and the anticancer effect by inducing apoptosis was confirmed, through an in vitro experiment. In order to examine the effect of DPL on cell viability, MTT assay was performed to confirm a significant decrease in the concentration of cell viability. DAPI staining was performed to examine the effect of DPL on cellular morphological changes and increase of apoptotic bodies. To supplement this, an increase in the apoptosis rate was also confirmed through flow cytometry after staining with annexin V/PI. Western blot was performed to confirm apoptosis-related proteins. DPL increased the expression of Cleaved-PARP, Bax whereas decreased the expression of Bcl-2. Changes in the expression levels of MAPK pathway proteins p-ERK1/2, p-JNK, and p-p38 were also confirmed, and a significant increase in p-p38 was observed. These results indicated that DPL induced apoptosis, through p-p38 MAPK signal pathway in SK-BR-3 breast cancer cells.

• Journal of Life Science
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• v.28 no.12
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• pp.1406-1415
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• 2018

Based on the antioxidative effects in organic solvent fractions obtained from the main methanolic extract of Houttuynia cordata Thunb, the cytoprotective effects by oxidative-stress were here analyzed. Regarding the antioxidant activity of organic solvent fractions, the electron-donating ability of DPPH increased in a dose-dependent manner, and $ED_{50}$ exhibited the highest concentration at $175{\mu}g/ml$ in the Hc-EtOAc fraction. The cell viability of Hc-EtOAc fractions on $H_2O_2$-induced HaCaT cell death ($IC_{50}$) increased in a concentration-dependent manner and a visible cell survival rate of 74% was observed at a concentration of $100{\mu}g/ml$. Meanwhile, the gene expression patterns in HaCaT cells treated with $100{\mu}g/ml$ of the Hc-EtOAc fraction for 6 and 24 hr were identified with microarray analysis. The genes involved in signal transduction, cell division, antioxidant activity, and epithelial cell proliferation were found to be 2-fold up-regulated genes in HaCaT cells following the Hc-EtOAc fraction treatment. Especially, proinflammatory cytokines (IL1B, TNF, and IL6) were identified as involved in antioxidant activity based on the expression patterns of the HaCaT cells, and pathway analysis indicated that TLR4 might be considered an upstream regulator of these genes. In order to verify the activity of IL1B, TNF, and IL6, qRT-PCR showed that the expression increased more than 2 times in HaCaT cells treated with at least $100{\mu}g/ml$ of the Hc-EtOAc fraction. The activity of the upstream regulator TLR4 protein was also increased by the Hc-EtOAc fraction. As a result, the antioxidative activity of the Hc-EtOAc fraction is predicted to pass from TLR4 through cytokines such as IL1B, TNF, and IL6.

• Journal of Life Science
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• v.30 no.12
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• pp.1092-1100
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• 2020

The six-transmembrane epithelial antigen of prostate 4 (Steap4) is a metalloreductase that plays a role in intracellular iron and cupper homeostasis, inflammatory response, and glucose and lipid metabolism. Previously, Steap4 has been reported to stimulate adipocyte differentiation; however, the underlying mechanisms of this action remain unexplored. In the present study, we investigated the molecular mechanisms involved in Steap4-induced adipocyte differentiation using 3T3-L1 cells, immortalized brown adipocyte (iBA) cells, and mouse embryonic fibroblast C3H10T1/2 cells. The knockdown of Steap4 using adenovirus-containing shRNA attenuated mitotic clonal expansion (MCE), as evidenced by the impaired proliferation of 3T3-L1 cells, iBA cells, and C3H10T1/2 cells within 48 hr after adding the differentiation medium. Steap4 knockdown downregulated G1/S phase transition-related cell cycle regulators (including cyclin A and cyclin D) and upregulated cell cycle inhibitors (including p21 and p27). Furthermore, Steap4 knockdown inhibited the phosphorylation of p38 mitogen-activated protein kinase, extracellular signal-regulated kinase, and Akt. Moreover, Steap4 knockdown repressed the expression of early adipogenic activators, such as CCAAT-enhancer-binding protein β (C/EBPβ) and Kruppel-like factor family factor 4 (KLF4). On the other hand, Steap4 knockdown stimulated the expression of adipogenic inhibitors, including KLF2, KLF3, and GATA2. The overexpression of Steap4 using an adenovirus removed the repressive histone marks H3K9me2 and H3K9me3 on the promoter of C/EBPβ. These results indicate that Stepa4 stimulates adipocyte differentiation through the induction of MCE and the modulation of early adipogenic transcription factors, including C/EBPβ, during the early phase of adipocyte differentiation.

• Journal of Life Science
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• v.31 no.2
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• pp.199-208
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• 2021

Euonymus porphyreus, a species of plant in the Celastraceae family, is widely distributed in East Asia, especially in Southern China. The botanical characteristics of E. porphyreus have been reported, but its antioxidative and anticancer activities remain unclear. In this study, we evaluated the antioxidative and anticancer effects of ethanol extracts of E. porphyreus (EEEP) and the molecular mechanism of its anticancer activity in human lung adenocarcinoma A549 cells. The total polyphenol and flavonoid compound contents from EEEP were 115.42 mg/g and 23.07 mg/g, respectively. EEEP showed significant antioxidative effects with a concentration at 50% of the inhibition (IC50) value of 11.09 ㎍/ml, as measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. EEEP showed cytotoxic activity by increasing the SubG1 cell population of A549 cells in a dose-dependent manner. Apoptosis in A549 cells treated with EEEP was evident due to increased apoptotic cells and apoptotic bodies, as detected by Annexin V and 4,6-diamidino-2-phenylindole (DAPI) staining, respectively. EEEP-induced apoptosis resulted in increased expression of the First apoptosis signal (Fas), p53, and Bax, with decreased expression of Bcl-2 and subsequent activation of caspase-8, -9, and caspase-3, leading to cleavage of poly (ADP-ribose) polymerase (PARP). Collectively, these results suggest that EEEP may exert an anticancer effect by inducing apoptosis in A549 cells through both intrinsic and extrinsic pathways.